HostGator have announced all of their shared and reseller servers are now wind powered...
green web hosting
HostGator goes green
Green web hosting providers
Running a website is tied to using electricity to run the servers, and it's a question how a sustainability minded person might run a web site in a sustainable way. This is a list of web hosting providers who take steps to be 'green'. In most cases they're buying credits to "offset" their carbon footprint.
Green web hosting at Dreamhost - a libertarian/capitalist's view
This libertarian is cheering private initiatives to save the environment - as much as I'm fearing government mandates. How chasing online profits led to an increasingly green lifestyle - free of driving, working on green web hosting, and even decreased consumption of excessively manufactured and processed foods.
Creating a Web Site for Your Green Business
One of the most important pieces of your marketing plan should be your company web site. Your web site will be the first impression many of your clients and customers have of your business, so it’s important to invest the time and money necessary to create a well-designed, informative, easy to use, and sustainable web site.
Australian Green Web Hosting
Digital Pacific is a web hosting company in Australia who has converted to using green power for web hosting. Everything used across business operations – including servers, routers and air conditioners are eco powered. Digital Pacific strives to create a socially responsible business and is encouraging and inspiring other businesses in Australia to do the same.
Nine Solar-Powered Web Hosts
With more and more Websites going online every day and adding more bells and whistles, Web hosting companies need more and more energy to keep their customers up and running. In fact, a recent study estimated that energy consumption by data centers around the world doubled between 2000 and 2005, and now amounts to the output of 14 power plants.

More Green Web Hosting
More discussion of green web hosting. Michael Bloch and AISO comment.