His and her Cheese Head Hats? :) Oh, right, everything.
I'm wondering why they are having a shower if they haven't registered enough items to cover the folks coming to the shower. Could you ask the person who is hosting the party for suggestions? Are you to attend the wedding, too? Therefore, will you be needing to purchase another gift later? What then?
I have purchased for myself and many others a nice basket at Whole Foods that is beautifully made and of which the proceeds go to those making the baskets, although they were in the $40-50 range.
Whatever you select, pick something you would be glad to receive yourself for the home. Ono has some great gadgets, or even go to Williams Sonoma or Crate and Barrel and find the best $25 gadget you can--something most people would NEVER spend that amount on for a gadget, but because it costs that much, it is an incredible addition to the kitchen.
That or a Kosir's Rafting on the Peshtigo River T-shirt. Have fun!