http://www.paulgraham.com/badeconomy.html
Here are some of his reasons:
1. "Technology progresses more or less independently of the stock market. So for any given idea, the payoff for acting fast in a bad economy will be higher than for waiting."
2. "It's not necessarily a problem if customers feel pinched: you may even be able to benefit from it, by making things that save money."
3. "Everyone knows you're supposed to buy when times are bad and sell when times are good. But of course what makes investing so counterintuitive is that in equity markets, good times are defined as everyone thinking it's time to buy. You have to be a contrarian to be correct, and by definition only a minority of investors can be."
It's a great post.
