Wall of Water

This is the shortest of the dozen or so featurettes found on the 2-Disc Special Edition Spider-Man 3 DVD. It consists of behind the scenes footage, interviews (almost exclusively with crew... the only actor is Thomas Haden Church, in fact) and movie clips. You get to see them dump the massive amount of water, which helps prove that it was, indeed, real, not a computer generated image. They talk about the efforts they made to ensure safety on set, the huge scale and they go into detail about how they did the effect.