Scoble's pointed me to Second Life. This looks like something I could get hooked on. He says you'll be able to blog, share music and do loads more stuff there. Think I might go try it out.
Update: BusinessWeek on Second Life, Red Herring reports that Second Life lands $11m to help the site become more mainstream, Second Life Slashdotted, Washington Post on Second Life: It's about the same things as the real world -- identity, status, seeing and being seen.