My main "side project" lately has been trying to get a job in the engineering side of biotech in the Bay Area. Meeting people is exciting! And part of this has been augmenting my blog [0] with some biology writing.
Other than that I've been helping my Google Summer of Code student with IHaskell [1] – soon we're going to have full widget support, supporting all the same widgets as IPython. Although I don't do most of the coding (the student is quite skilled and incredibly productive) I get the satisfaction of seeing something awesome being implemented for IHaskell!
[0] http://andrew.gibiansky.com [1] http://www.github.com/gibiansky/IHaskell