I have seen some pretty cool electronic graffiti techniques in the past, but multimedia performers Sweatshoppe's method—which uses a paint roller to draw video straight on walls—beats them all.

The paint roller doesn't paint anything on the wall. It's made with green LEDs. A camera next to the projector tracks the position of the paint roller, unmasking the video projection in real time, as the artists draws on the wall. Pretty clever.

Sweatshoppe—artists Bruno Levy and Blake Shaw—plan to release the software as soon as the polish it and beef it up with features. [Wooster Collective via Bonnie Burton]