Apple's diminutive MacBook Air line of laptops is built for lightness, filled with solid state storage for efficiency, and this year's model packs more than 13 hours of battery life into a single charge.

But one thing nobody ever accused the Air of being is a graphics powerhouse. Intel's integrated HD Graphics 5000 GPU, which powers the latest generation of Airs, just isn't designed for churning out cutting edge graphics.

Those limitations didn't stop Larry Gadea, who spent about $250 recently to build a homemade external GPU enclosure that turns the Air into a bona fide gaming machine.

Check out the video above posted earlier this week on Gadea's YouTube channel to see Borderlands 2 running on an 11-inch MacBook Air courtesy of an external GTX 570 eGPU, a power supply and a bit of hardware translation between its PCI Express card interface and the MacBook Air's Thunderbolt port.

You can also learn all about making your own in a detailed post on the Tech Inferno forums.