What Do You Bring on Long Trips or Rescues?

After looking at some pictures and videos of Members on long trips or heading out to pick up their new project, it sure would be handy to have a good checklist of "must have", "probably going to need this", "not needed, but will make my life easier", and "leave it at home".

(And no, you can't say one of those giant. 200 draw, roller tools chests.)