According to the official Second Life blog, a problem at their ISP has forced them to take Second Life offline “until further notice”. Further notices have been posted already, but they’re pretty much the same as the previous notices: SL is borked, come back later.
As US senator Ted Stevens pointed out a couple of years ago, the Internet is in fact a series of tubes. I’m no expert, but I think a really long plumber’s snake would probably clear the problem right up. See, whenever someone’s hair goes missing from their inventory, it just ends up clogging the tubes.