I recently had to create a word document that was a little more complex than your everyday word document and I had to do it without Microsoft Word. So, without my security blanket I learned how the competition stacked up, or did they?
OpenOffice
The first application I ran to was OpenOffice, the hyped up alternative to MS Office. While the interface isn't nearly as slick much of the functionality from MS Word is duplicated well.
One of the tasks I had was to place a 'text box' (a.k.a iframe) in the top right corner of the page with some information and this proved to be the downfall for OpenOffice. I just couldn't get it to work right. The functionality wasn't very usable. It did everything I needed except this. Since I couldn't figure it out, easily, in a few minutes it was time to move on to the next guy.
Sorry OpenOffice, usability seems to be a burden you carry.
Google Docs
I quickly jumped over to Google Docs to see if I could create my document in there. This has become my main document editor and the reason I have no license of MS Office on my computer. But, some of the advanced functions weren't available so it was time to move on.
Zoho
Next up, I tried Zoho Writer. Zoho provides a suite of web based productivity applications from document editors, spreadsheets, and presentations, to CRMs, invoicing, and other business applications. Many of these applications are free to use.
With Zoho writer I was able to create the document I needed and in fairly short order. The interface is not the most beautiful, though it does reflect MS Office. But, for me it got the job done.
For anyone interested in Zoho, they have integration with Google Gears, MS Office, and more.

acrobat.com and buzzword
check out buzzword, and how it collaborates within the acrobat.com environment. very slick
whups...
forgot to include the URL...
http://buzzword.acrobat.com
Thanks For the Link
I'll have to check this out. Thanks.