Johannes Schlüter has a recent post highlighting an interesting PHP extension that can connect memcache with your MySQL server via PHP, the PECL mysqlnd_memcache extension.
Now this blog entry is tagged a s PHP. Hs is that coming into play? - Well, on the one side we have this fast memcache interface, which allows to access almost arbitrarry data from the database. On the other side we have our PHP mysqlnd plugin interface where we can add special features, like query caching or load balancing, transparently to any PHP application. Why not combine those two things? - Good question. That's what we have done in the PECL mysqlnd_memcache PHP extension.
He includes some sample PHP code showing it in action - two examples: one using the "mysqlnd_memcache_set" method to set a memcache server on the MySQL connection and another showing two queries and how they're handled behind the scenes by this driver plugin.