business (2)
NeoOffice
http://www.neooffice.org/
This is OpenOffice repackaged in nice looking Aqua goodness and using Java as well. Don't need that slightly clunky X11 for this one.
PHP Point of Sale
http://www.phppointofsale.com/
Free POS system if you need it. You might want to look into installing MAMP first.