I'm not entirely sure what use I will make of this, but I thought it was interesting and, I think, largely unknown.

If you use Google's image search as normal and then add "&imgtype=face" (without the quotes) to the end of the URL for the results page, and press , you'll just get images with faces in. Try 'libarians' (scary) or, say, 'astronauts'.

You can also add &imgtype=news to get images associated with news items.

Have a good weekend!