You bring the code.

Facebook gives you the massive distribution .

Joyent gets you rolling for free, and has the compute cloud infrastructure ready to handle scaling your application to millions of users.

This is game changing. Now, you really can build a Web business, get real users and not need a dime of upfront cash for infrastructure. Sure, you still have to figure out how to generate revenue, but Rock You and Slide are proving that is certainly possible.

Imagine going into a VC and explaining that you have 2 coders, 800,000 users, a real revenue stream and ideas about how to grow even bigger?

Or, perhaps even more likely, if you are doing an interactive marketing effort that leverages the social graph, you can test it out before committing to a big spend… or more likely, a long fight with your internal IT. A great example of a company that has already done this with Joyent and Facebook is Kinzin. They currently use Joyent to host their “Are you normal” application, which they have scaled to 180,000 450,000 users with no issues.

The program of free Accelerators is only open to the first 3,500 developers who sign up. After that, it’s not free, but it is cheap. Only $45 per month to get rolling with a Joyent Accelerator in a data center that is peered to Facebook. That means no latency issues and no suprise bandwidth bills. Do video. Do games. Build whatever you want.

This is going to be fun.

There’s more here: Joyent Announces Free Hosting For Facebook App Developers