LETSystems: Very Simple CC Framework.
Coventry LETS trading since 1993 as paper-based soft currency
PyLETS web-based accounting helps as afterthought
Basing new LETS on LETSystem agreements and web support sustainable & bridges digital divide better than paperchase.
Still need: Social events & newsletter or trading dries up. Outsource?Multi-Registry Systems: Information exchange protocol/framework making use of many CCs (systems), many users and registries feasible.
Status: PyLETS practical/production use, MRS experimental, R&D.
MRS reliant on DNS for object naming, ultimately DNSSEC : http://www.dnssec.net/
Use of CC likely to stay very small scale until end of 'legal tender' taxes : http://copsewood.net/writings/kaytax.html
Reputation framework to transfer credit rating between systems ? If reputation manageable in decentralised manner with email, same problem solvable in connection with decentralised CC.
Value leakage or strong identity? Probably based on private agreements. Will biometric-based identity systems outcompete non-biometric ?