CES 2013 - Digital Storm's Bolt system is a mere 3.6 inches wide - tiny by today's standards for gaming systems - yet, it supports up to a GTX 680, the fastest single GPU on the market. This system's case is custom designed by Digital Storm, and, like the Aventum, is fabricated locally in the San Francisco Bay Area.
The system starts at $999, and for that, you get an Intel Core i3 processor and NVIDIA GeForce GT 650Ti. Of course, like all of Digital Storm's systems, this one is highly configurable and can accept up to an Intel Core i7-3770K. You're probably wondering how they have managed to shove a full size GPU into such a small chassis. Well, they use a riser card to flip the GPU parallel to the motherboard.
The CPU features a side-panel intake with a 120mm fan and the GPU is fed cold air by a side-panel blower. The system, considering it's size, stays cool, even while playing demanding games for extended periods of time. You can get your own Bolt at Digital Storm's website.