This is a two-parter at cross purposes:
I'm interested in converting some gym equipment I have lying around to act as input devices for my computer, and I'm looking for interesting applications. While I can easily generate keystrokes to control any game (walking in World of Warcraft is a popular example), I'm surprised that I'm having a hard time finding more directly applicable games. For example, I'd love to find a cool bicycling simulation program where the brake levers are analog controls. I know a lot of hardcore racing sims have robust APIs to let you add your own custom physical dashboards and controllers to the game; what other interesting examples have you seen?
This one is different. What exercise equipment out there has an open API to let send commands / control various settings programmatically. Example: an exercise bike with programmatically settable resistance through a USB or serial interface. I ask because I have some pretty specific interval programs I'd like to be able to do, but every computerized elliptical/exercise bike/treadmill I have access to at the gym have shortcomings in their built-in programs that don't match exactly what I want to do, and I started fantasizing about making my own controller.