Grockit
(closed Beta is coming soon waiting list)
an online learning game where people can teach each other.
update 12/12/2008:
Grockit has been released.
dotspots
(email waitinglist)
DotSpots is a universal annotation system that brings the wisdom of crowds to every meme (block of text) on the web, and leverages automatic semantic matching to distribute each contribution to every instance of that meme across the web.
hangout.net
(email waitinglist)
Now you can customize your own room, fully interact with friends and your favorite brands, and share media experiences in an immersive 3D environment.
update:
hangout now is in public beta.
Bojam
(email waitinglist)
Bojam is an online music collaboration service connecting musicians to mix, record, and collaborate to produce original or popular music.
gooseGrade
(email waitinglist)
The tool allows readers to critique and suggest corrections to bloggers and other online authors.
update:
gooseGrade has been released.