Ideas for wedding pranks?

My fiance and I both have a great sense of humor. We want everyone to have fun at our wedding/reception, and we were toying around with playing a prank on all of our guests/bridal party/groomsmen. I've been looking up stuff, though, and all of the pranks seem to be either directed at the husband and wife-to-be, or are just...well, lame. What if we want to prank our guests, or each other? Any suggestions? The more original, the better, because there aren't many pranks my family hasn't seen. Thanks!