The Google Summer of Code is a event I got involved as a mentor for Pidgin. Pidgin, Gaim at the time, was accepted the first year and has been back every year since.
2005
I mentored 3 students in 2005.
2006
We didn't get as many student slots in 2006, and as a result, I took a break, and had the summer "off".
2007
In 2007 I mentored Eoin Coffey. I had worked with him briefly after GSoC '05, since he applied for the Mono Plugin Loader, but another student was chosen for that project. So in 2007, we took the work that Eoin started in 2005 and continued on with it. He finished his work for the summer, and deserved the "pass" that he got.
His work was merged in but does not currently build by default. The reasoning for this is the way in which libmono works. Due to it adding it's own signal handlers, it makes it look like every libpurple crash is in the Mono Plugin Loader. It's unfortunate, but this is a show stopper, until there is a way to change this in libmono.
2008
In 2008 I mentored Justin Rodriguez. His project for the summer was to implement a generic and UI abstracted theme mechanism into libpurple and Pidgin. He finished our predetermined goals and was given a passing grade.
Justin's code has been merged in and will be available to all starting with Pidgin 2.6.0.
2009
Currently I am mentoring Eric Polino who is working on moving the objects used in libpurple to GObjects. This is a crazy big project that requires all sorts of refactoring among other things.