My first AppEngine app. It collects exceptions in Rails apps, ala Hoptoad and Exceptional, but has about 10% of the features.
Get JRuby and some gems...
git clone git://github.com/jruby/jruby.git cd jruby ant && ant jar-complete bin/jruby -S gem install rake sinatra haml warbler
Download Exception Collection and run warbler to get the tmp/war directory...
git clone git://github.com/seven1m/exceptioncollection.git cd exceptioncollection PATH_TO_JRUBY/bin/jruby -S warble
Go to tmp/war/WEB-INF/gems/gems/sinatra-0.9.1.1/lib/sinatra.rb and commend
out the last line which is
Upload to Google AppEngine or test locally with the AppEngine SDK.