I like this stopwatch app called MyStopWatch. Simple, easy to use, has a few nice functions (including countdown timer). I attached a cab (it's Freeware - everyone's favorite!!)
EDIT: This is a really nice app. Has multiple timers (so, your meter expires in 1 hour, you can set reminders in 50min, 55min, and 1 hour), has a nice gui, different alarm sounds & vibrates...