CouchDB: Thinking beyond the RDBMS. CouchDB is a fascinating project—an Erlang powered non-relational database with a JSON API that lets you define “views” (really computed tables) based on JavaScript functions that execute using map/reduce. Damien Katz, the main developer currently works for MySQL and used to work on Lotus Notes.
Sign in with 
OpenID
I haven't quite 'got' the views bit, but is the rest much different from a mysql table of structure
id Integer
data Blob
and then storing serialised data in the blob?
I'm waiting to see if CouchDB provides enough relational support - all data is relational to some extent...