Green Tips - Union of Concerned Scientists blog and newsletter on everyday changes for greener living.
Ecological footprint calculator from Earthday.net. An interesting way to gauge how much impact your everyday life has on the environment. A list of suggested changes after it's finished would be nice. Carboncounter.org has a good calculator too, including an option for precise calculation based on energy and gas bills. Also, you can use Personal Kyoto and input your ConEd account number to see a record of your energy usage and then try to bring it down 25% - the Kyoto goal.
Stop Global Warming has a good list of habits to change. It's the same list you see on many other sites, but clear and succinct here. It's aimed at suburban dwellers, though. An urban list wouuld be handy.
Carbon offset purchasing
Carbon offsets remind me of the practices of buying indulgences for your sins from the Catholic church in past centuries. It doesn't make what you do get any better, it just makes you aware of the externalities that your activity generates. The difference between carbon offsets and indulgences is thatyour offset purchases presumably are really going to pay for things that will reduce the overall amount of carbon emissions.
Banking & Investing
Light Green Advisors - an investment advisory service that provides investment options that are environmentally and financially sound. Here is their list of portfolios. Thanks to Adam Black for the link.
The Social Investment Forum - "The Social Investment Forum site offers comprehensive information, contacts & resources on socially responsible investing."
Green Supply Line - Advice and articles on business practices and purchasing decisions. Thanks to Wiley Bowen for the link.