Fred Wilson's recent blog article "Startup Porn" really rings a bell.
I strongly encourage you to read the article if you haven't already. And do subscribe to Fred's blog AVC.com if you're a volume reader.
My point would be: good startups are created in both good times and bad times. If you create a product or service that's truly, fundamentally attractive, you'll be able to manage the cash burns well and survive the bad times and achieve successful exits when the good times come.