Cornell University Grows a Synthetic Tree

Scientists at Cornell university made a synthetic tree out of a water transporting tissue called xylem, which has hydrogel capillaries. This material allows water to evaporate at a very similar rate to trees. They use hydrogel in contact lenses as well. Since the synthetic tree was a success, they have ideas of using them to heat offices and other buildings, and also possibly use it to cool down computers.

Here's a link to the article at Wired.
http://blog.wired.com/wiredscience/2008/09/a-synthetic-tre.html