What are some good online note annotation sites?
Ideally, I'm envisioning something that allows you easily to take structured (indented lists / outline form) notes in class and organize them properly. If I were to build something myself I would include the ability to attach a .ppt or .pdf so one could view lecture slides alongside their own notes, but that is wishful thinking.
I've come across stu.dicio.us, which looked promising, but they appear to be down for the time being.
Any ideas, or should I make this a Christmas break project of mine?