Taking Pictures at Popular Tourist Sites Minus the People

"You're at a popular location and you really would love a photo of the place without all the people in the way. Looks like you're out of luck and you should just buy a postcard, right? Not with this clever trick."

The end result is pretty cool, but unfortunately the end result requires Photoshop, a very expensive tool that most people don't own. A comment in the Lifehacker thread mentions an interesting alternative: using an ND filter to allow long exposure times. The idea being that with a long enough exposure, most people will move in and out of the frame, essentially blurring away. You'll need to fix the clouds up after though, so make a snapshot of the clouds separately. Boy, seems like a lot of work, doesn't it? Maybe it's better to just yell "MOVE!" really loudly. ;-)