Here's what you do . . .
Hold the egg so that your fingers are on the ends of the egg. Tap the side of the egg firmly on the countertop (not the side of the bowl). The tap should be firm enough to create a little crushed, flattened portion on the side but not so firm that the inside of the egg is exposed yet. Then, over the bowl, use your fingers to break the egg apart.
Supposedly, cracking it on the countertop (or other flat surface) rather than the edge of the bowl (or sink) keeps the internal membrane intact and keeps small shell shards from breaking free. Who knew?
(This tip made its way to me via my Real Simple magazine. Love it! :)