At Couchbase we recently introduced an open source SQL-style language with extensions for nested data. Live tutorial: <a href="http:&#x2F;&#x2F;query.pub.couchbase.com&#x2F;tutorial&#x2F;" rel="nofollow">http:&#x2F;&#x2F;query.pub.couchbase.com&#x2F;tutorial&#x2F;</a><p>We get a lot of folks who start with a Mongo evaluation and end up moving to something more serious.