Saturnalia is a distributed time series database designed for indexing stats. Saturnalia is available as Open Source under the MIT license and currently hosted over on Bitbucket.
We also have a mailing list over on Google Groups if you'd like to join and collaborate with us on using Saturnalia in production.
We're currently in development mode right now but expect to have a beta release available shortly (November 2011).
Feel free to contact us directly at support@saturnaliadb.org. If you'd like for us to email you when we launch, please enter your email below: