A note of support for Trent at The Simple Dollar, who just removed all Google ads because of ethical conflicts. Since Trent has over 20,000 subscribers by feed alone, this was no small decision.
Like Merchant Ships has a no-ad policy for similar reasons. I feel uncomfortable showing you how to save money and--at the same time--encouraging you to buy.
Circumstances may change, but for now, I feel good about this choice.