Word… online
Writely‘s target is to bring a fully-featured word processor on the web.
Currently in beta version, Writely.com allows to sign up for free and to use the word processor application developed by their team. No need to install any software, everything is usable from the web browser: with a couple of clicks you can create a new document and start writing, with (almost) every text-formatting option.
There’s some limitation (the first you’ll notice is the lackness for the available fonts , that are, of course, the ones that are standard for the web), but in general this online application works, and it allows also to import Word docs from your PC. There’s also an (experimental) function to export in PDF format, but this will be, probabily one of the future optional features for paying users.
The “Collaborative” are remarkable: they allows, for example, the possibility to edit together with other users the same document, at the same time, and to have the document automatically saved in every revision, to avoid the risk to lose some important part of the text.