Anyone written widgets and/or Facebook apps before? →[More:]
I run an events calendar as part of a site I administer, and I've been casually trying to extend its accessibility.

I have developed a Yahoo Widget, but haven't had success with the UWA (Netvibes' "universal widget architecture" -- perhaps there's something I'm mising out the development process?), and can't develop iPhone or OS X Dashboard widgets because I don't have either technology. (I have OS 10.3.9.)

Now I've developed a Facebook app but I'm trying to figure out exactly what I'm able to do with it. I have ideas but I'm not sure what the platform allows. I've found their documentation kind of lacking -- some of their wiki links don't even resolve to anything -- and lots of what's out there is from before their big overhaul a few months ago.

Anyone worked on this stuff and want to chit-chat about what they've done?