Reader Robert asks:

What criteria do you use to determine if a stock is overbought?

Robert, I'll be the first to admit "overbought" is somewhat subjective.  Still, I think that condition is fairly easy to spot when you're looking at a chart and it really consists of 2 key elements: 1) a steady -- almost unrelenting -- move up.  2) No pullbacks during the move up.  

As an example, see almost ANY chart the past week, but in particular the S&P: