Affordable Internet Services Online (AISO) is now offering web hosting, colocation, and some other services at their facility in Romoland, California. The cool thing about it is that the whole data center is powered by solar! I looked at the prices, $9.99 for web hosting, with a comparable plan to many other vendors offering similar services.
With most typical data centers running at about 4,000 watts per square foot, we will probably see more systems like these. Their setup seems pretty advanced (Here is their heat removal system) - this alone reduces their cooling bill by 70 percent.