I've just heard about Shuter Clock.
So at 9pm, not 8pm, take a photo and join in. 9pm is after sunset annoyingly.
ShutterClock is looking for happy clickers all across the world to take part in a global camera event happening this year. On May 11th 2007 at 8PM GMT time, camera users will take photos in unison and create a gallery of images taken at the same moment. ShutterClock wants you and all your friends to take part in this global picture gathering.
So at 9pm, not 8pm, take a photo and join in. 9pm is after sunset annoyingly.