I wouldn't be surprised if Valve made a port of Steam running Linux based scripts and resources that could boot Windows-made games. They may potentially make "SteamOS". I would see that as in innovative way to do things but the problem is the Linux/Windows hybrid idea for games. Although, I do agree on the building of a custom system in an mATX form factor, such as a BitFenix Prodigy, or the Cubitek case.