From the New Scientist:

First impressions are highly influential, despite the well-worn admonition not to judge a book by its cover. Within a tenth of a second of seeing an unfamiliar face we have already made a judgement about its owner’s character – caring, trustworthy, aggressive, extrovert, competent and so on (Psychological Science, vol 17, p 592). Once that snap judgement has formed, it is surprisingly hard to budge. What’s more, different people come to strikingly similar conclusions about a particular face – as shown in our own experiment (see “The New Scientist face experiment”). (full story here)

Wouldn’t this would make an interesting art unit?