Whenever I am involved in any programmer hiring decisions, I will always ask for a portfolio. Lots of people won't have it, and that will say a lot about them-namely, that it is likely they did not write anything worth carrying with them. I will also ask what they hack for fun. If the answer is "nothing", the liklihood that they are a workaday programmer or a larval manager is very high.

Speaking of managers, there is a corollary for them. Managers accumulate people as they work. The quality of those people will say a lot about them.