Anthony McCall is a British artist who makes what he calls 'solid light' films--explorations of beams of light as they encounter various densities of air particles presented by vapour, smoke, fog, etc.
I've sadly never seen this in action (there's a piece languishing in the SF Moma's permanent collection vaults!) but the description alone is enough to make me swoon! I've always wanted to do this sort of thing with sound...
