I always take:
Standard Allen keys
Metric Allen keys
Crescent wrench
Pliers
Needle nose pliers
Mini needle nose pliers
Multi-head screwdriver
Dental pick
Autococker valve tool
Angel tool kit
Mousepad
Loc-tite
Macro line and fittings
Assorted O-rings
Autococker-specific O-rings
Angel-specific O-rings
Angel AIR rebuild kit
ACI Air lube oil
WDP Lovejuice oil
WDP lovejuice grease
White lithium grease
C clip pliers
Trigger springs, main springs, misc. springs
Soldering iron, solder, shrink tubing and electric tape
I think that's about it, there may be one or two things I'm forgetting. And I'll second what was said before, it still seems like I don't have the one tool I need.