I have a TA peanut butter wrench that I wrapped the handle of with inner tube. Use it all the time on my fix gear hubs. (But the Pedro's fix gear tool with spanner goes on my rides and gets used almost as much. And, sadly, its spanner is far better for 12t lockrings than my big Park spanner is. I love the Pedro's. That and a custom 16 oz cog wrench make doing fix gear cog changes on the road a piece of cake.)

My favorite tool? (And a little out of topic - I really don't care what the brand name is, but the tool itself means enough to me that I bought a house for it.) A bench vise. Most useful tool by far. Gets used to make some if the most useful parts on my bikes. Real pedal pick-up tabs that I can get first try at intersections on my fix gears. Tabs that do not bend when I step on them and last for years without ever looking at them again. It is also a good third hand for hub cones.

Ben