Every bowler has her own technique, so it's fun to mess with that by playing Funky Bowling. For each frame you play, use a different technique to bowl. For the first frame, have your fellow bowlers bowl their normal way. For the second frame, have them bowl with their opposite hand (if they are right-handed, they bowl with their left hand). For the third frame, have them bowl with both of their hands (also known as "granny style").
Have everyone stand on one foot and hop for the fourth frame, and then bowl backward (between their legs) for the fifth frame. For the sixth frame, have bowlers sit on the floor and roll the bowl down the lane. For the lucky seventh frame, have three team members form a tunnel in front of the bowler, stand with their legs apart. The bowler must throw the ball through the tunnel.
For the last three frames, have bowlers cluck like a chicken when they toss the ball down the lane, throw the ball in slow motion, and blindfold or close their eyes (though have someone watch the bowler, otherwise you could have a bowling ball landing somewhere it should not be landing).
Rather than bowling the conventional way, you can add bingo to the mix. During bingo bowling, which you can play one-on-one or with teams, the winner is not necessarily the player or team with the highest score.
Before you start playing, fill in the 25 squares on a bingo card with results that usually occur during a bowling game. You can fill the card with results such as the number of pins a bowler knocks down (0 to 9), gutter ball, strike, spare, head pin only, no head pin, 2 strikes in a row, number 7 pin only and free space (you put that in the middle square). Every time a player or team member achieves a result that's on the bingo card, have them mark it off. The first player or team to mark off five results appearing horizontally, vertically or diagonally shouts "Bingo" and wins the game.
You can add some levity to a regular bowling game, even without unorthodox techniques or bingo. Every time a player steps up to bowl, choose a category and have the bowler shout out as many items that fit the category as she can before the ball hits the pins (if it in fact does). For instance, you can have bowlers name American states, farm animals, movies or music stars that emerged during a particular decade or reasons they consider themselves great bowlers.
You also can have bowlers count backward from 200 (or the number of your choice), or recite the alphabet in reverse. During the game, keep track of how many items bowlers could name during their turns and award bonus points on top of their regular score.