Vim is an amazing text editor that will...oh wait, sorry.
Wire cutters. Seems simple, I know. Having bad wire cutters, though, is a sure fire way to un-inspire students to go into electrical engineering.
RJ-45 crimping tool is a tool you may never use, but when you do use it (like in the middle of competition when your tether cable gets cut with your great wire cutters) it'll work wonders.
Multimeter is a fine tool that will tell you whether or not you correctly wired your 8P8C plug on your RJ-45 tether cable.
Leaterman. When all else fails, in the end, you know you provided your team with as many tools as possible to get the job done.
Last but not least, a
nifty little bag. Because you want to keep all these cool tools in the same place, why not do it in style?
Just some simple suggestions from a programmer turned electrical guy for 6 weeks.
PS. I know this thread is mainly for big manly tools, but you'd be surprised how many people don't have the basic tools.