I carry a Topeak multi tool and a spare innertube depending on the ride.
The biggest irony is that tool has fixed everyone else's bike except my own. For instance down on the Bodmin Camel Trail, we came across a bloke on a brand new Raleigh trying to put his crank back on by hand.
mars bars haribo
tubes x2
topeak alien
chain tool
tyre levers
allen keys
spare m5/6 bolts
small shifter
small first aid kit
pump
£10,47 in cash
some mud
glueless patches (look to be past their best tbh)
another multitool (free magazine one )
small LED lights
Cool tool /Topeak multitool (depending on which camelbak is picked up)
3 inner tubes (1 is none, 2 is 1 etc)
Tyre levers
Leeches
Pump
A few spare links of chain
Few quid in change
Snickers bar