For a few years I've carried a Protech Godson (very high-quality switchblade) on my belt, and it's come in handy many times when I've needed to cut open a box or something, but I've often found myself in need of pliers or a screwdriver, especially for a minor repair on my bike.

I used to carry a Leatherman tool with me all the time, but I lost it and never replaced it- I just picked up a new Wave model- it came with a cheap nylon sheath rather than the leather sheath that used to be supplied (it now has to be purchased separately), but otherwise it's a great tool, and everything can be opened one-handed.

I looked at the Super Tool model, but it's an inch bigger and bulkier (though it comes with two more tools and is a bit cheaper) but most motorcyclists recommend the Wave (which comes with a couple of extra screwdriver bits).

What do you carry?