This is a very easy little contraption to build that makes a sort of ripple in your pictures (note: you will need a smaller lens on your camera for this to work.

Step 1: Materials

glue or tape
plastic wrap (try using colored plastic wrap for cool colors)
toilet paper or paper towel cardboard tube
camera

Step 2: Putting It Together

Take your cardboard tube and get a piece of plastic wrap that's just a little bit bigger than the cardboard tubes opening and tape or glue it on so that it ripples in the middle.

Step 3: Using It

Hold your ripple effect creator up to the lens of the camera if it is to long and you see the cardboard cut of the edge until its small enough then twist it until you see the proper ripple effect then snap your photo. :D