The High-Low Tech group at MIT's Media Lab set out to turn the cell phone into an object that's easy to customize and personalize without breaking the bank. They created their prototype with an SM5100B GSM Module that takes a standard SIM card and a custom circuit board. Here, the original prototype before being shrunk down to fit on a customized circuit board.
Making the first call with the prototype -- "Watson come here, I... Whoa! Were you standing back there the whole time?" It's no smartphone, but voice, texting, and other slightly old-school functionality is possible.
The naked prototype is a retro-tinkerer's dream. "Freed from the constraints of mass production, we plan to explore diverse materials, shapes, and functions," the project page reads. "We hope that the project will help us explore and expand the limits of do-it-yourself (DIY) practice."