I have found another unique site. This site is not a commercial business site, but associated with science and outer space. This site called hellofromearth.com. the goal is to send a messages from the inhabitants of the earth that is sent to the planet Gliese 581d. Planet Gliese 581d found by scientists in April 2007 this is the only planet that can support life suspected of being habitable zone (read more about Gliese 581d in). Through this site, you can write a message addressed to the inhabitants of planet Gliese if there does exist a form of life. The messages you'll send them through a device that can reach planet Gliese, the message estimated will arrive in the year 2029. If you are interested, try to visit hellofromearth.com for more infos.
Plus, read my article about this planet gliese 581d that I write for bukisa.