During the spring, Dynamo asked me to upgrade the Yellow Bird Project to the latest version of Spree (at the time this was v0.50.2). The challenge for this project was managing the upgrade from a forked version of Spree, pre v0.9.0 back in 2009. One tool that was really useful was using Max OS X's FileMerge to compare database schemas, allowing me to determine what the new schema would and determine any naming conflicts with custom tables added previously.
The upgrade resulted in an application that can now be easily upgraded to future version of Spree and runs on a more stable, scalable platform thanks to Heroku.
The Yellow Bird Project is pretty cool - they work with a range of indie rock musicians to create some neat t-shirts that then benefit a charity chosen by the musicians themselves. So put away that ugly university hoodie and go get yourself some cool threads.