Put the roll of coins in your palm and punch yourself repeatedly. Good stuff man! Quarters might work better though. It's a personal preference.
...a sock may work better for this task... but try them both, and let us know which works better (do this before you put them up your ass)
buy $5 worth of bazooka gum, collect the comics and make a book. for 5 cents a pop, the comics are a great read.