I just found this link on twitter and it’s a really good read. The author mentions a few points on how to identify a good programmer and I agree with all of them. Check it out:
http://www.inter-sections.net/2007/11/13/how-to-recognise-a-good-programmer/
I really enjoyed this article. Not only can you apply it to programmers, you can apply it to other creative fields as well. Surprised at the negative feedback.