Yep! I would actually recommend NeoOffice over OpenOffice. They are both free and they're both exactly the same code, but OpenOffice is a Linux program that will only work in OS X if you have X11 installed. It also has Linux-style buttons and menus and dialogs, so it can be frustrating for Mac users (the open and save dialogs can be really funky).
NeoOffice is OpenOffice compiled for Mac rather than Linux. You don't need X11 installed to run it, and all the buttons and menus and such are OS X looking rather than Linux looking. It also runs a bit faster in my experience.
