The Visual Music blog gathers snap shot of websites that document work, artists, filmmakers, composers, musicians, video artists, exhibitions, call for worlds and events that work with the art and medium of visual and sound. All forms and presentations are considered. This blog contains an extensive archive as it has been active since 2005.

Graffti Research Lab

http://graffitiresearchlab.com/
Dedicated to outfitting graffiti artists with open source technologies for urban communication.
One of their events is:
"The Graffiti Research Lab will be in Rotterdam from February 7th through the 10th (2007). We’re taking control of the Renzo Piano KPN Telecom Building and turning the Kop Van Zuid into the People’s Revolutionary Green Laser Light District. We are turning the 37 x 72 meter screen into a place to display your uncurated animations and graphics"