This one never saw use with bicycles, but imy favorite because I made it from a discarded aquarium air pump as a teenager, to vacuum-extract brake fluid from disc brake calipers on motorcycles.
By putting a machine screw under one edge of the cylinder, I was able to tilt the cylinder enough to reverse it's action, from pump to vacuum. Added a one-way valve to improve it's performance.
Found use recently extracting an extra quart of fluid from the pan of a modern "sealed for life" automatic transmission, since each pull of the drain plug was only removing 1.8qts out of 7 quarts in the system.
The motor gets really hot within a few minutes, no doubt why this 1950's(?)-era relic was discarded back in the70's. I doubt that I'll ever rewind the motor's coils since it's never left unattended, though one guy almost burned his fingers on the motor housing recently while I was bleeding his mc's brakes.