Since late 2012 we have been using GitHub to manage our source code repository for the SolarNetwork project. Get the latest and greatest here http://solarnetwork.github.com
Until recently nodes have run a full version of Ubuntu or similar full blown Linux distribution. We now have our own minimal Debian OS image specifically configured for running SolarNodes. Details available here: http://sourceforge.net/apps/trac/solarnetwork/wiki/SolarNodeBuildGuideDebian6