SilverlightDevCampSF is an upcoming gathering, inspired by BarCamp, to build Silverlight applications, It's organized by volunteers & Silverlight enthusiasts, with attendance free to all. It's the same weekend as Adobe MAX, but Adobe MAX costs $1,495. This is free to attend. Plus you can help plan it or lead sessions with a simple edit of the event wiki page.
While similar to iPhoneDevCamp this event is focused on a singular technology, we'd like offer some diverse sessions like using PHP to generate Silverlight content, IronRuby/IronPython & the DLR or Moonlight on Linux.
Attendees will include web designers, developers, testers, all working together over the weekend to build Silverlight applications, share experiences, and push the limits of web application design.
Official Website: http://barcamp.org/SilverlightDevCampChicago