Choosing an Arduino for Your Project
The e-textiles segment of the Arduino market is ruled by LilyPads. These are identifiable as unique purple, flowery-looking, circular boards. The pins on LilyPads are called "petals", they have bigger holes and copper filled to the edge of the board. These are designed so conductive thread can be sewn through the holes, and make electrical contact with the exposed copper on the petal.
LilyPads are great for e-textiles -- projects which combine electronics and fabric wizardy. For a detailed explanation of these boards, check out this tutorial.