Earlier quoted context omitted.
Would it be legal for someone to manufacture and sell 3rd party Steamboxes, if Valve has no immediate plans to do so? It seems like somebody like Alienware, or even just somebody on Kickstarter, could put together something impressive at a XBox720/PS4 pricepoint.
You might want to talk to valve before using the word "Steam" in the name of your product... Otherwise I can't see an impediment. Maybe Valve could even have a 'designed for Steam' certification program or something.
The MistBox ;)
I don't know, though. To be honest, I'm kind of shocked no one has tried this yet. It seems like such an obvious winner, even if there is a slight chance you would go to court with Valve.