Engadget has the first look at iBuyPower's prototype for a Steam Machine PC, which is due to be released in 2014. It looks nothing like a PC, instead taking a page out of the Guide To Designing Home Video Game Consoles.
There are two variants, with a "light bar" that seems to be able to change colour, which is neat.
The overall design is nice and subtle, if a little too similar to a PS4, though that power button and GIANT STEAM LOGO look a little naff. Then again, this is a prototype, so there's always time for improvements.
If you haven't seen it, here's what Valve's own prototype unit looks like.
You can see more shots of the unit - including its range of light bar shades - below.