Charles Max Wood of Teach Me To Code Screencasts has put together a 13 minute screencast demonstrating how to use some Ruby metaprogramming magic along with Rack in order to build a small Sinatra-esque webapp framework. Watch the HD version at Vimeo or download the video to get the best quality.

Charles is also trying to raise a little money to help him get to RubyConf and do some coverage from there. If you enjoy this screencast, I'm sure he'd love a few bucks (and might sing your praises into the bargain).