Skype has been PostgreSQL as their back end database and have made available their database projects as part of the Skype Developer Zone. For background how Skype has made us of PostgreSQL check out the whitepaper.
Skype has made the following projects available:
- PL/Proxy
- SkyTools (made up of Londiste, PgQ and WalMgr)
- PgBouncer
- Enhancements to PL/Python that are part of PostgreSQL 8.2
Nice to see Skype giving back to the PostgreSQL community.