3D Street Art
The website is a little clumsy, but there are some really cool projects here, including The Crevasse, The Waterfall, and Lava Burst. There are also several videos showing how the artist puts these perplexing pavement paintings together.
For an interesting application of this idea, check this out: a 3D pavement painting of a child playing in the middle of the street! The idea was to get the attention of speeding drivers. I bet it did just that!