It's Electric!

Above is a video of the trike just going down the dorm hallway and back in the first iteration after hooking up the electronics.

I ended up finding a 48v 1000w, 26" hub motor kit for a good price (now discontinued) on Amazon....I guess they really do sell everything.  It included pretty much everything I needed to get started, except for the batteries and an inner tube on the wheel.

Roberto helped me out and showed me how to make a battery pack using 3.3v LiFe A123 cells.  I started off with 2 6S2P packs, which won't bring me up to 48v, but the icharger 1010B+ model that I picked up only charges up to 12S.  They worked well though, and I went ahead and used electrical tape to mount everything onto what had once upon a time been the chain stays on my bike.

Kinda Ride-able State

We really tried to include all the bells and whistles, including the folded-towel seat and plastic grocery bag to keep the electronics dry.  That was about it for the first testing design.  It turned out to be surprisingly fun to drive despite being slightly difficult to control, and the tight turning radius made the trike optimal for spinning stunts: