When it came time to pit a pound of cherries that were destined for baking, I caught this pair, flush-faced and perspiring, reminiscing about their wild treetop days.
How to pit cherries without a pitter
Unwind a small metal paper clip into an S-shape.
Insert the smaller of the two bends into the cherry's stem end (keep the stem on even).
Trace a small circle around the pit.
Hook the loop beneath the pit and wiggle it up and out, pulling on the stem to help extract it.
A (clean) bobby pin works too.