RockYou, widget maker, is the latest example of a sane valuation heartbreaker, as it is undertaking efforts to secure an investment from mainstream financing firms that would value the company at between $300 million and $400 million.

First reported by Valleywag last night, the start-up, said one source, “is being squired around Wall Street” by investment behemoth Morgan Stanley (MS), in search of the same kind of deal its rival Slide got in January.

BoomTown broke the news of that deal, which nabbed Slide $50 million and a $550 million valuation with investments from blue-chip investors T. Rowe Price (TROW) and Fidelity.

Thus, RockYou’s motto: Anything Slide can do, we can do slightly smaller!

And, indeed, not to be SuperPoked by Slide CEO and Founder Max Levchin, sources said RockYou Co-Founders Jai Shen (also CTO) and Lance Tokuda (CEO) were quickly on the march for their own payday.

It is, in fact, a quest that a lot of Web 2.0 companies seem to be on, since the sector’s fearless leader–Facebook–got its $240 million and $15 billion valuation from Microsoft (MSFT) last year.

All of this frantic funding activity is, of course, this bubble’s version of going public–grab big cash investments from investment firms and hedge funds, desperate for a good bet on the sector, without the pain of public scrutiny of questionable business prospects that did in Web 1.0 shooting stars.

It’s that or get bought for an ungodly sum by equally desperate Web 1.0 companies (See: AOL+Bebo).

Sources close to RockYou, which has had acquisition feelers put out to it from larger companies in the past, said the company has had several strong offers of funding, but it is trying to select the right partners for the latest round of funding.

“We want our investors to be strategic and helpful to the company,” said one person close to RockYou.

RockYou has so far been funded by Sequoia Capital, Lightspeed Venture Partners and Partech International.

(Interestingly, Sequoia backs another instant messaging and chat widget maker, Meebo, which is reportedly seeking a $250 million valuation, which I posted about here yesterday).

To be fair, makers of highly distributed third-party apps like RockYou are garnering immense traffic and their widgets are syndicated everywhere. RockYou’s Super Wall, which lets you turbocharge your digital wall, for example, is one of the most popular on Facebook.

Other RockYou apps include: X Me, a communications tool that allows you to “Hug Her, Slap Him, Tickle Them!”; and Likeness, where you can “compare yourself with friends and movie stars like Angelina Jolie, Jessica Alba, Keira Knightley and many more.”

The company has been trying to monetize all this traffic and popularity and distribution, as well as knowledge of user behavior, by offering advertisers new forms of engagement.

But the jury is still out on these interesting but unproven efforts by all the social-networking players.

In any case, the money is apparently still flowing into these start-ups, taking a chance on them being the next big media play.

Here are two videos I made when I visited RockYou’s offices in San Mateo, Calif., last October, after I had called the widget market juvenile and faddish.

The first is my tour of the office, where I was playfully accosted by an infant–oops, a RockYou engineer–in a suit. The second is my interview with Shen and Tokuda.

So I recently ventured into the heart of the empire of toddler developers with a visit to the San Mateo, Calif., HQ of RockYou, the super-popular maker of third-party apps on hot social-networking sites like Facebook and MySpace.

I have been on a bit of a grumpy tear of late about the juvenile nature of these widgets, whose use has taken off explosively, as the sites they live on have grown.

I have felt that most of them have been a bit silly, useless and faddish, rather than long-lasting and relevant.

RockYou’s apps, for example, include: Super Wall, with 1.26 million active daily users on Facebook, which allows you to turbocharge your basic posting wall; X Me, a communications app with 706,000 Facebook users, which allows you to “Hug Her, Slap Him, Tickle Them!”; and Likeness, where you can “compare yourself with friends and movie stars like Angelina Jolie, Jessica Alba, Keira Knightley and many more,” which has 611,000 active Facebook users.

Like another widget maker, Slide (I did a post and video on Slide here, as well as a three-part interview with founder Max Levchin too), the start-up has big VC backing. In RockYou’s case, it is funded by Sequoia Capital, Lightspeed Venture Partners and Partech International.

Of course, there are the rumors of big-money buyouts and even IPOs for these developers.

I am not so sure this is a good thing, but I do also believe there is something important going on with companies like RockYou, which could become akin to the major software makers of the past era. If, of course, they grow up a bit first.

Here’s my video of a visit to their office (and here is an accompanying interview with its co-founders Lance Tokuda and Jia Shen), where one employee jokingly played dress-up just like an adult, sporting a suit and tie just for me.

Oh, those crazy kids!

Right now on Facebook, I have been trying to decide what to do near on two weeks or more, after receiving a “Hot Potato” tossed to me by my old boss, Washington Post Co. CEO and Chairman Don Graham (oh, yes–his family also owns a key hunk of the legendary paper, too).

For those who don’t know what a digital Hot Potato is: It is a widget (also called a third-party app) created by a very nice-looking group of guys at a design outfit called Hungry Machine for the Facebook platform.

“You have to pass it on and watch it travel around the world. 27,012 other people did!”

With all due respect to Don Graham (who is a mentor of Facebook founder Mark Zuckerberg, by the way), Hungry Machine and all world-trotting spuds, I don’t think so.

I get it, I get it. Millions upon millions of people are downloading and using these apps, part of a very clever ecosystem Zuckerberg unleashed in late May.

Under the scheme, widget-makers got to go wild on Facebook and Facebook got to offload a chunk of its feature development onto others. (See my movie below of the f8 launch, including a somewhat awkward Zuckerberg on the stage.)

At that event, a 750-person jeans-and-T-shirt-clad army of Web developers gathered at the San Francisco Design Center’s Concourse and began to create even more apps in earnest with an all-night hackathon.

“Until now, social networks have been closed platforms,” said Zuckerberg at the event, calling on outside developers to integrate their applications into the service. “Today, we’re going to end that.”

But, so far, as popular as those apps have become, what Zuckerberg and the widget-makers have wrought is mostly silly, useless and time-wasting and the kazillion users of these widgets are pretty much just acting like little children.

I never thought I would call the often frivolous AOL back in the day–very simply, a Neanderthal version of Facebook–a mature offering in comparison.

While I will admit when I am not chewing nails that a lot of these apps are somewhat fun, I can’t help but ask myself that lyric from the old Peggy Lee classic: “Is that all there is?”

And if that is all there is, can Facebook really build a viable and long-lasting business on what is essentially a bunch of games that will ultimately become wearying for users? Doesn’t it need more robust apps that actually are useful and relevant and make Facebook the service that Zuckerberg has often told me was a “utility”?

While Facebook–with a cleaner and more strict look and a better navigation–is surely less goofy than rival MySpace for anyone over 12 years old, and its video, photo and email features are nice, the vast majority of its apps are still mostly as dumb as a box of hammers.

Maybe they will attract scads of ads and maybe not, but first consider the top apps on Facebook right now.

Slide’s No. 1 Top Friends, which has 2.94 million daily active users, lets you “add a box of up to 32 of your BFFs to your profile.”

Wheeeee! Paris Hilton forever!

Not to pick on them particularly, as I think they are great developers (see my post on Slide here), but Slide’s FunWall (2.2 million) lets you add lots of bells and whistles to what is essentially graffiti-writing.

And its SuperPoke (1.16 million) is just plain rude when it notes, “Why just poke when you can pinch, hug, tickle, pwn [sic] or even throw sheep?”

Sheep? SuperPoking? I’d be getting queasy if I were a Procter & Gamble media buyer right about now!

iLike (694,000), with its music recommendations and sharing, is all well and good, but also light.

And X Me from Rock You (673,000)? “Tired of just poking? X Me opens up a whole new world of action-based communication, for example, ‘Hug Her, Slap Him, Tickle Them!’”

Oh no, you didn’t.

What else? Vampires. Werewolves. Naughty Gifts. An Honesty Box where you can say gross things in messages anonymously.

And my rececent favorite, which grew 4,107% the other day, called Pop Ur Zit!

To give you the entire feel for it, I am printing their whole reason for being below (plus this lovely cartoon above):

Another usual day…. With half-closed eyes, you are headed to the bathroom…OH MY GOD!!! It’s the Zits!!!

“Pop your zits at your friends and gross them out!! But you can also rescue (soothe) them with your favorite products. It will cool them down, relieving their stress as well as changing their biorhythm.

“See what happens every 10 hours and see what you can do by popping your friend’s zits. Zitometers will sync with your actions and time. Be aware of alerts on zitometer. Your friend’s soothing is the only way you can get rid of your zits on your face.

“You will get rewarded for being a kind soother. Your rank will go up as you soothe more people and you will get different coupons to use on hundreds of shopping malls.”

Is it just me?

No, thankfully. Wired Editor and “The Long Tail” author (who should know about this stuff) Chris Anderson wrote about the Facebook apps market in a post, which was actually a reaction to another analysis report by Tim O’Reilly.

By way of background, Anderson noted that O’Reilly’s report showed that Facebook apps were “top-heavy, with the top 84 apps of the 5,000 analyzed having 87% of the traffic,” before moving on to the obvious conclusion of why this was so:

1. The social networking on Facebook is too powerful. This is the tyranny of network effects, where viral success is the only kind and popularity snowballs into an avalanche or goes nowhere at all. That sort of herd behavior is usually a sign of an immature market.
2. Most apps are total crap. That, in turn, may say something about the whole idea of Facebook as a platform. But I’ll leave that discussion for another day.”

So, let’s discuss. And no potato-throwing, please.

Next chapter: Why I don’t really want to SuperPoke, say, Digg’s Jay Adelson, on our 2,500-person strong D: All Things Digital group on Facebook? But what else is there to do?