I run a Cateye Enduro, the heavy-wired kind, on both my mountain bike and the commuter. Nice & simple for tracking time and mileage, and has a pace arrow feature, which I like to try and keep in the "up" position whien pedaling along ;-)

I have a mount on the left handlebar where I can mount my Garmin Vista handheld for when I'm running in trail-of-breadcrumbs mode.

Haven't been real trustful of the wireless versions just yet, but then I'mmore than a little bit of an old fogey about these things...