have each guest bring a package of diapers-in different sizes and then just put their names in a bag and choose one as the winner...they get a prize and you get a ton of diapers that you will need!!
We also always play the cotton ball game. have the person sit in a chair with a bowl of cotton balls on their lap and blindfold them and then have them spoon the cotton from their lap to a bowl on their head that they are holding. It is hilarious to watch because you can't feel if you have any or not, thinking you have a lot in the bowl on your head and sometimes you only have 1 or 2...LOL cute game! good luck with your shower and congrats on the baby!