I never hit the trail without the following
29er tube
26er tube
patches
mini pump
co2
inflator
basic multi tool (choose one that meets your abilities if you cant use a tool no need to have it)
seperate chain tool
quick links (yes more than one you never want to give away your last one)
knife
duct tape, thread, wire, needle, and other mcgyver ish things
Never forget to have more food and water than you need