On May 5th's podcast they announced that starting June 6th you'll be able to play along with the Buzz Astroblaster ride on your PC. They obviously are expecting a lot of hits on this - they mentioned a "queue" for playing online and the opportunity to win Fast Passes to play right away.
disneyland.com/buzz has the following info:
Buzz Lightyear Astro Blasters Interactive Experience(Coming June 6, 2005!)
Connect live to Tomorrowland and team up with Guests in Disneyland® park to save the universe from the Evil Emperor Zurg. Compete to win a place on the high-score board by lighting up real Theme Park targets in this out-of-this-world interactive adventure.
Sounds like it's going to be fun! At least it'll kill time until it's time to GO.