OpenOffice (I think it's called) is freeware. I know my aunt was using it for work stuff. It has all the same extensions (and probably others that aren't Word-specific)

My daughter used OpenOffice http://www.openoffice.org/ when she was in college VERY similar to Word (and Excel and I think other bits of the Office suite) but its free.

I use google docs, which is free.

I had to relearn some functions, but i thought free was worth that. It isn't as snazzy, but it does lend itself to bets reading

There is Abiword

Google Docs and

Open Office

I've never used Abiword, but Open Office and GDocs are both similar to Microsoft word (and they are all free.) Hope that help some.

I see there are already suggestions for Open Office. That's what I use, but lately when I edit a document created in Microsoft Word the formatting gets lost easily and it's a lot of hassle to fix once I get back to Microsoft Word - if it's even possible to fix

Another solution, if you don't mind putting out a small amount of money monthly, is a subscription to Office 365 for $6.99/month. Also, if you're a student, you can get a free subscription.

If not, I fully support both Open Office and Google Docs, they're both very easy to work with once you figure out where everything is.

I also use OpenOffice. :o)