[olug] Point of Sale/Bookkeeping cross-platform?

[Eric Lusk]

I'm in the process of planning a business launch.  In this process, I'm looking for an Open Source alternative to something like Quickbooks.  Basically, I would love to have something that runs POS, tracks inventory, prints bills, etc.
It also would be highly beneficial to have it run on client/server, for automated backup.
I've got PCs to install to, and it would be so much simpler to have a Linux based POS system for me.
Has anyone seen/used anything like this?  Of course, I'm already browsing Sourceforge for an idea, but any input would be great before I download half a dozen different apps...

 I ran the Harry Potter books through a spell checker; none of those spells should work.