i havent read through yet but the impossible situp is a great trick, or waiting until everyone is on the ice and tossing all their clothes into a garbage bag and only leaving panties and diapers for them to wear.
squirting dudes in the shower with dish soap and then turning the cold water off (usually in teh ceiling right by the shower) is great.
perfuming jerseys is funny
take a box cutter and slice right down the middle of everyones laces and then have a box of pink ones ($60ish) for them to use.
i played on a team one year where the year before some dude threw 2 live chickens into the dressing room, i didnt see it but it was supposedly hilarious.