This is a neat little book I stumbled across a while ago, but recently found is available for free on Google Books. Essentially, it is a list of 507 different mechanical movements compiled in the 19th century, with illustrations and a small blurb describing each one. Not all of them are relevant to FRC, but it would make an interesting pdf to flip through while you try and think up new game piece manipulators. At any rate, it's a neat little book to get you thinking.
507 Mechanical Movements