[RandolphF]

Anyone know some good ones? I don't need lists of stretches; I need a capable, configurable timer.

[MJKearney]

I'm not sure if this is quite what you're looking for, and it's certainly not sports activity specific, but Timers4Me is very customizable and configurable. You could set up timers for all your different stretch routines, and give each timer its own name. They have a free and a paid version. This is the free version:

[fmya]

Try Workout Timer