I'm giving Paul something I know he will like: an annual pass to the Sci-Fi center at EMP in Seattle (since that is where we will live after the wedding). They even have Captin Kirk's chair, which I guess is a cool thing.
BUT--I am also giving him something that we can both enjoy. I am making a scrap book / photo album of our life together up until the wedding. It will have plane/train tickets, concert/movies stubs and photos as well as postcards, recipts, and brochures/business cards from places we've been around the world. My thought was that after the rehearsal dinner, I would take him to my faviorite spot in my home-town and share the album with him. Sort of a walk down memory lane so that we remember how it was that we came to walk down the aisle in the first place.