Make Onesis
Buy enough short and long sleeved onesis for all guests (preferebly a little extra in case someone makes a mistake), rubber stamps with animals, letters, baby things, etc.; acryllic paint, paint brushes, paper plates, and baby wipes.
Have each guest put a onesi over a paper plate so that paint doesn'wt seep through to the back of the body onesi. Paint on the rubber stamps and create body suites for the baby. Use baby wipes to wipe off paint brushes.
Guess how many safety pins
Fill a jar full of safety pins and pass it around to each guest. The guest who guesses closest number of pins gets a shower prize.
Guess the baby picture
In your invitations ask each guest to bring a baby picture of themselves. Number the pictures (not on the actual picture) and have the guest guess who's who. Whoever gets the most correct wins a shower prize.
Mommy's Tummy
Have each guest cut a piece of string that they think will fit around Mommy's pregnant tummy. Which ever guest is closest recieves a shower prize.