Topeak Mini Morph
This pump is the smallest, lightest pump that you won't throw off a cliff in a fit of rage if you have to use it.
With a foot peg, short hose, and fold-out T-handle, it's a breeze to inflate tyres to a high pressure.
Comes with a mount to go underneath your bottle cage.
Fits Schrader, presta and Woods (Dunlop) valves.