Here are some pictures of a “box guitar” that I recently built. It’s sort of like a cigar box guitar, only rather than finding a pre-built box and scratch-building a neck for it, I bought a guitar neck, and scratch-built a box for it.
I picked up a neck from a new, but broken Cort acoustic guitar, and a cheap soundhole style pickup on ebay. The pickup came pre-wired to tone and volume pots (tone doesn’t seem to do anything though) and knobs were included. The rest of the materials I had on hand, so build cost was under $40 dollars for this project, including paint and a set of 10′s.
The sound is kind of banjo-twangy unplugged, and it has an interesting howl when plugged in. Here is a Garageband sample. (forgive the playing).