K.,
Here are a couple of things that I just happend to see in an idea notebook I had.
#1 use cloth diapers as napkins at the shower, then launder them and give them to the new mom for burp cloths (or diapers if she is using cloth)
#2 Buy a package of newborn disposable diapers and at the shower open them up- give everyone a permanant marker and let them write words of encouragement, helpful advice, or their own funny baby story on the diaper itself (the outside of the diaper) and bag them all up when everyone is finished. The idea being that the new mom can only read them one at a time at each diaper change after the baby arrives.
#3. Have a frozen casserole shower (if the expectant mother has already had a lot of gifts or if this isn't her first baby and she doesn't need much). Everyone brings a casserole already frozen, with the recipe (bring lots of coolers to store the food until it can be put back into a freezer)
Good luck and have fun