Working on set in the studio biz, everyone has a multi-tool. I've seen them all, with saws, leather punches, magnifying glass, etc. When it comes down to it, the things you use 90% of the time are pliers, knife, screwdriver and (after work) bottle opener.
The Skeletool by Leatherman wins hands down and at 5 oz and around $60 is the way to go. You can also get a 24 bit accesory set for the screwdriver:
