Posterita POS is a fully functional free web retail POS that caters for large distribution, multi-sites and multi-terminals. It makes large distribution effortless with its intuitive and user friendly interface as well as its revolutionary feature that gives 100% uptime even when offline.
It is totally web based with modules such as accounting, stock management, reports, barcode, user and role controls and purchase control system among other features.
It is written in Java and is platform independent (MAC, Linux and Windows).
See the demo on http://demo.posterita.org
Free SAAS soon http://posterita.com