I was a huge David Letterman fan when he had his NBC "Late Night" show. (I check out the "Late Show" on CBS every once in a while, but it's not required viewing for me anymore.) I watched Dave just about every night, and he was always coming up with goofy and off-the-wall stuff.
One of my favorites was when he'd drop stuff off a five-story tower in New Rochelle, NY (among other places). Bowling balls through TVs, a bunch of watermelons all at once, that sort of thing.
Here's a great clip from the mid-1980s of Dave doing just such a thing. Never ceases to crack me up. This is number 23 on the countdown. Enjoy.