Roll Up Your Sleeves and Go!
Yes, we do already have a whole category for games in which you can vent your frustrations in all kinds of ways, but not all those games are about slapping things around, and sometimes that's just what you want. In these games you can slap at random without alienating your friends. Play a celeb and whack away the paparazzi who are harrassing you, spank the inflatable monkey, or go on a rampage as a belligerent drunken leprechaun. Roll up those sleeves and get ready to go!