A puppet show. It would show you spent some time, thought and effort on her, and that you weren't just trying to find another reason to show her your underwear and the "treasures" within. Write a script, get some socks set up, practice, and amuse the sh!t out of her.
I know, it was kind of inspired, wasn't it? I almost deleted it to keep for myself, but then I realized that my wife's computer is in here with mine, so, it would be kind of lame for me to try, since she would see it on her computer at the same time I would be right there bumping into her chair and stuff doing the voices crawling around on the floor. So, wtf, might as well hand the muse's gift along, eh? Probably will become a major Internet sex trend, and you will be the only person besides myself to know that it started right here with this question and the large handful of beers I have had thus far. lol. I'd list the ideas I've had that have become huge thusfar that I swear were rip offs, including pointing out the Geico commercial with the woodchucks that came out coincidentally after my Another 10 Most Asked Questions in the World hub... but hey.