So let's say you're in Prague on the 600th anniversary of the construction of the Prague Astronomical Clock and you want to have a good time. What do you do? Make a fantastic video and project it onto the entire face of the clock tower, which is quite a feat given the dimensions of the tower. The video below shows what happened -- 10 minutes of animation on the tower, showing among other things: the construction of the tower, its inner gears, luminescent rain, various wars, and floaty astrological symbols reminiscent of a Twilight Zone credits sequence. Also, because it's a tower, it's a really tall video. Weird enough for you yet? Click if you dare.
For more information about the clock, its history, and photos of it without all sorts of stuff projected on it, check out its Wikipedia entry.