In the darkroom I teach at we are equipped with the ol' time-o-lites, they are simple and easy to use, but the timing over short periods such as 1-2 seconds can vary a bit. there is also a lack timing anything under a second.
At home, I started out with the gralab 300, way too big but a fun thing to use. Again the accuracy wasnt the best over short spans. I have upgraded and have been using a gralab 451 for awhile now. It is a nice small timer, not much bigger than the time-o-lites, I have it mounted on the wall next to my enlarger, it allows for 1/10 second increments, very visible red leds, metronome, countdown timer, and foot switch. It is a very good timer in a compact package.
I would like a Fstop timer, but the prices are a killer. Then again its not to hard to do the math in the head anyway.
You can always do it counting as well and flicking the enlarger on and off too. My dad did this for contact printing when he was growing up.