BSOD stands for Better Sounding On Drugs and is Steve Duda vs. deadmau5.
Although BSOD broke up some time ago Deadmau5 still performs BSOD tracks. Deadmau5 and Steve Duda are close friends, and often tour with each other.. due to Deadmau5' common success Duda tends to travel with Deadmau5 often. The two are currently working on a piece of software similar to 'FL Studio' in ways, to go on par with their sample collection they released some time ago..

Read more about BSOD on Last.fm.