While he is out on the water get a floor jack and move his ride in the parking lot.

Give some kid of a different ethnicity some ice cream money to run up & hug him while hollering daddy daddy daddy

Don't forget to get some real rank ones from a street skank

Wire up a relay to lock his horn on the first time he uses it

1/4 ounce of skunk oil on the cockpit deck

If his wife/girl friend doesn't know you walk up to him and say "Dude your wife isn't gonna like you hanging out with these strange women"

Did I get the "sick puppy" award yet?

fvcking hilarious.... this one gets it for sure...

Or just swap props. Forward=reverse, reverse=forward.

This works great........ After leaving the dock (be far away) ask what are these spare drain plugs doing in the cup holder and toss them overboard as your buddy is recollecting what they would be doing there!