I'm going to keep this to hand tools.
1. All of our rivets are set by hand, and some members of the team don't have the strongest grips to use our
normal rivet guns.
This one makes short work of even 1/4" rivets and can be used by almost everyone. It's smaller than the really large hand rivet guns that Harbor Freight or else wear sell so it fits into more spaces.
2. Another great tool I don't see enough teams using is a simple pair of
aviation snips.
These combined with 1/16" polycarb can fix a lot of problems on a robot.
3. High Torque Ball End Hex Keys - These have been mentioned by other people on Chief before but they are fantastic. This year we have added colored heat shrink to all our hex keys to make identifying them easier. I also like the
screw driver versions as well.
4. Cheap ratcheting wrenches - if you look on ebay you can regularly get ratcheting wrenches for under $3-5 each. We bought a ton of 3/8" since we normally use #10 hardware.