Some time ago I got around to creating a profile in Facebook, when a friend invited me to do something or the other on there. No, I really don't remember the circumstances. Now I'm a bit addicted to Facebook, despite certain annoyances in how it pushes applications you're using on to your friends. (Yes, I realize that would work for some, but everyone doesn't work the same way.)
I'm fascinated with the simplicity of Facebook's architecture, and the power it produces. Each application is basically a function you can apply to data, which is the list of your friends. Each use of an application generates a message to all your data. There's a bit of window dressing to go along with this basic idea, such as being able to search for friends and applications, managing email, etc. But there really doesn't seem to be that much more to it. The only other social networking site I've tried is LinkedIn, which by contrast seems quite static. But then it does so much more with that static structure. Would it be possible to implement LinkedIn on Facebook?