I can't remember if anyone mentioned a tool that stays attached to me everyday--- a GOOD pocket knife. When I wake up in the morning, I check to see if my wallets in the back pocket, knife in the left pocket, and tape on the right! I don't know if anyone changes their own tires anymore...... but a good long wrench you can jump on to get bolts off tires is nice to have in the car...... for those of us that aren't super strong!
I can't remember if anyone mentioned glue or bungee cords. Another thing I would add, although, again, I'm not sure if anyone besides me still uses these.... but a good ole fashion miter box! You can do a lot of things with that, assuming you don't have a miter saw. Although, I still grab the miter box my grandfather made and used from time to time.... like most hand tools, they're often quicker then power tools, believe it or not.
My dad still buys me those little sets of screws/ nuts that come in a little plastic box that have a bit of everything in them. They're nice to have.
Above all, get them a nice hammer...... a new one is no good. I say this largely because the feel of a worn wooden handle is just awesome. There's no two ways about it.
cheers,
bird