Robohash.

Robohash is a web service that makes it easy to provide unique, robot/alien/monster/whatever images for any text. Put in any text, such as an IP address, email, filename, userid, or whatever else you like, and get back a pretty image for your site. With hundreds of millions of variations, Robohash is the among the leading robot-based hashing tools on the web.

I typed in 'The Generator Blog' and this is what I got.

(thanks Luis)

[ Robohash ]