What are some of your favorite sites for free-lance writers?

http://freelanceswitch.com/ is pretty good for writers and designers.

http://www.freelancewritinggigs.com/
http://www.freelancewriting.com/
http://www.sunoasis.com/freelance.html
http://www.writersweekly.com/
http://www.journalismjobs.com/index.cfm
http://www.mediabistro.com/
http://jobs.worldwideworkathome.com/freelance-writing.html
http://www.bookjobs.com/index.php
http://www.2work-at-home.com/index.shtml
http://www.writersdigest.com/GeneralMenu/

Now you know all my secrets. Good luck.

I usually write for companies. I agree with ljs22 that Media Bistro is a good resource. I know several other freelancers that get assignments from there as well.