[richardbrevig]

Seriously, though, this looks a LOT better than the other services that provide this. They're often based on "acceleration" and direction of the cursor. So, I usually set them off just while going to click on a link. If this really only goes off when the person takes their mouse off the screen, bravo. I also noticed in a comment on here that it only goes off once per user per site: again, the competition have (at least it seems to me in memory) hit me with their "don't leave us" screen multiple times on the same visit.

Summary: this has 2 superior functions their competitors don't have.