The tool I currently have in my backpack is Topeak Power 21, a predecessor of the current Tool Monster. Would buy again, if it still existed. It's light! The two main pieces together are 3.9 oz on my kitchen scale. (The current version is more than 6.) Has the advantage of omitting moving parts. I did recently strike out trying to undo a SRAM derailleur whose bolt was too deep for the bit. I've lost the tire irons and whatever that hook thing is.

Hey, looks like they are going for twenty or thirty bucks on eBay



If I were getting one today I think I'd like to try Fix It Sticks, they use standard 1/4" hex bits so you have the tools you need for your bike, and they can be replaced if you round them off. There's a deluxe kit with a chain breaker and tire levers, and there are torque clutch accessories if that's something you want. Admittedly short on end wrenches.



I always supplement my bike tools with a small Leatherman knockoff, and there are some tiny scissors in the first aid kit.