My new favorite fetch trick:
Throw the tennis ball really hard, making sure it bounces once off the
far wall.
Dreyfus picks up the initial toss, but almost always fails to track
the ball as it bounces off the wall and flies back over his head.
Eventually he figures out that the ball is behind him, then he
does a 180 and turns on full afterburner to get to the thing.
All of which, of course, makes for a great photo opportunity as
he blazes past me on his return trip.
I'm sure my upstairs neighbors hate me by now :-).