Abiword 

A free multi-platform word processor. It is open source so maybe you can help develop it but on visiting the site you will see that numerous plugins have already been developed. AbiWord will run on virtually any operating system with a minimum of time spent on porting. This combined with support for internationalization (the ability to run AbiWord in many languages) gives AbiWord a massive potential user-base.

AuthorIT

The ultimate single-sourcing tool. Write once, reuse many times, maintain in one place, publish to multiple outputs, a truly single source environment. AuthorIT provides a system in which digital information can be created, stored, managed, controlled and published from a single source to print, online and help formats. I believe this will be the future of documentation as file management has been built in to the system allowing multi-users in certain versions.

TextMaker

Now here is a word processor that works on the move. The program is available for the PDA as well as the PC but unlike the transfer of Word between your PC based version and the PocketPC version it does not lose its formatting. It is also compatible with Word so you can do your “foreigners" on your PDA on the train, in the pub or wherever, format it, put it onto your PC when you get home and open it in Word and send it to your customer