Use a toothpick, un-bent paper clip, or, my favorite, orange stick (as for manicures), and insert into the stem-end of the cherry. You should feel it hit the pit.
A reader (Diane from Vinalhaven, Maine) wrote in saying her family had used a lobster/crab picking tool - the kind with a small scoop on the end of a stick - to great effect. I'm looking forward to trying it next time I sit down with a few pounds of cherries!
