Even though they're not expensive, it's never fun to run out and purchase an over-the-air antenna. If you're looking to patch one together on your own, Make user Rich Reynolds shows how to do it on the cheap by attaching a soft drink can to a transformer.
The process is incredibly easy. First, cut a soft drink can in half, then staple the two halves to a piece of wood, hot glue a wire to run from the cans to the transformer, and you're done. It's not the prettiest solution in the world, but it's also easy to hide your creation behind the TV. In the end, it's probably less noticeable than a set of rabbit ears and seems to catch just as many channels. Hit up Make for the full guide to make this for yourself.
Over the Air TV Antenna [Make Magazine]