I'll second the above mention of NeoOffice. It's now aqua. It's totally free, very handy, and handles more formats than anything else. I've used it for 50 - 70 page academic papers with very little trouble. (far less trouble than word has caused.) You can open and save .doc files if you need to.
Or, if you want to stick with supporting free software, you could just install OpenOffice on your PC - it's the PC version (and predecessor) of NeoOffice. Free and great.