Online word processors

Seeing I'm talking a lot about word processors today (see post below), let's look at online word processors. An online word processor gives you the ability to create, edit, save, and access your documents from anywhere. You can start your document in Christchurch, and finish it in Auckland. The best ones also allow you to share documents, track changes, revert to earlier versions, and collaborate with other writers, some of them in real time. Best of all, any reasonably up-to-date computer can access them, usually without installing anything. Some require ActiveX, Flash, or Java — all of which are already present on most computers – but depending on your system or the quality of your broadband, they may sometimes work at slow speed.
A quick search came up with a list of at least 10 free services, of which Google Docs is probably the best known. There are probably almost as many again that work in more specialised ways. But here's my quick list:
Google Docs
Zoho
Buzzword (owned by Adobe)
iNetWord
ThinkFree
EtherPad
ajaxWrite
Box.net Web Documents
docly
Peepel
Many of the above are part of an office suite, containing also spreadsheets and maybe presentation software. The big upsides are the free service and the ability to collaborate with people in different locations without having to shuttle files around. One of the downsides, though, is the big unknowns regarding security, and whether you want critical data stored on the internet rather than on your hard drive.