POT is a persistancy layer that lets the programer persist almost any thinkable object tree.
It can be found at http://pot.forgeahead.hu/
Its similar to ThePrevayler but lets you create a object tree in any way one feels like.
Questions:
The above link does not currently respond. There is more information at http://directory.fsf.org/sysadmin/Backup/POT.html