I got one of these from Performance Bike a while back and it's all that I ever need:



Mine says "Performance Bike" on it but it's the same tool. Park has different versions of the same thing.

I find many of the fancy McGuyver-type multi-tools to be bulky and awkward to use (especially the ones that come apart and come together like jigsaw puzzle pieces), and most of the added "extra tools" just don't work well half the time. I carry a spoke wrench, a small Park chain tool, and a light-weight Spyderco knife separately and with all these I've managed to repair all the "difficult" mechanical problems I've encountered on the road, including broken drailleurs, finicky brakes, bent rims, snapped spokes and broken chains.

-Kevin