Peter K?nig has been a big name in producing concept art for some huge projects over the years. He's been at Valve since 2008 as a concept artist, modeler, texture artist working on Dota 2, Left 4 Dead 2 and other projects. His website now shows a host of interesting new Left 4 Dead 2 concepts as well as a space ship with SOB 49 written on the side.
Late last year, the Dota 2 leak contained some info on this previously unknown Valve IP 'SOB' which suggested it was a game set in space with space ships of some kind. A picture on Peter's blog in 2011 (now removed) can be seen below in comparison to the updated image now on his website Hard Surface / 3D Concepts section. A scrapped project or soon to be announced?
Peter K?nig responded to an email of mine (smash) about the mysterious concept art that was found on Valve's wall in early 2011, and I would like to share it. I asked him if that art was for practice or production, and this was what he said: