The price is right game, purchase a couple baby items from the registry (that I gifted to her later of course) and created a simple card where guests had to guess the price. I set out the items on a side table for them to look at.
Non-Awkward Baby Shower Games and Activities (this is both kind of corny and maybe kind of nice - pages for a baby book that people could fill out. we'd customize, of course.)
Baby Shower Games write on diapers and write question on card and next person writes answer on the back.