I only now of two free hosting agents, and neither are very good. The first is a .tk domain (go to my.dot.tk ) which I haven't personally had any experience with, but they force an add frame at the top of the browser (so it's always there, even when you scroll down). The other is a .co.nr domain (go to
http://www.freedomain.co.nr/ ). They are little better. The claim "no forced adds". There's only a forced animated .gif, which promotes .co.nr names.

they also don't give the option to have a DNS service (even a third party one), so you can't have subdomains etc. The same people which do .co.nr, do .biz.ly (go to
http://www.biz.ly/ ), which seem the best of all, but you need to have a high traffic site before they'll give you a free domain.
On top of that, I've come across a few free webhosting places that will give you a free domain name (.com, .org, etc) if you stay with them long enough (sorry, can't find link).
I still think you'd be better off though, to do what karyuu suggested an get a cheap domain name. I've got one myself that I haven't used that much for only $12US. I'd be carful with GoDaddy though, I've heard that if you go to register a domain, and cancel halfway though, they'll hold that domain for "premium" members, and you'll have to pay extra, or something... I could be worng.