NeoOffice is a fully-featured set of office applications (including word processing, spreadsheet, presentation, and drawing programs) for Mac OS X. Based on the OpenOffice.org office suite, NeoOffice has integrated dozens of native Mac features and can import, edit, and exchange files with other popular office programs such as Microsoft Office.
Pros: NeoOffice is a free and easy-to-use alternative to Microsoft Office. Unlike the Mac OS X build of OpenOffice.org, NeoOffice runs natively, supporting such native features as fonts and printing, under Mac OS X.
Cons: None significant.
Note: NeoOffice is Mac-only, but native builds of OpenOffice.org are available for Windows, Linux, Solaris, and FreeBSD.