Designer, Plusea, created this solar-powered t-shirt with an integrated electronic necklace. A motor mounted on the shoulder runs continuously or in short bursts, depending on how much sunlight is available. The result "tickles" your cheek at variable speeds. This would make me want to sneeze all day, however, the designer put together a great tutorial on how to make this wearable on instructables so that DIYers can get an introduction into soft-circuits and wearables.
Pulsea also considered washability by integrating the circuitry into the t-shirt using conductive fabrics and threads and keeping all of the non-waterproof electronic components built into a detachable necklace so that it can be removed when washing the t-shirt.
Check out the project's flickr set here. And a recent workshop here.