http://www.neatorama.com/2007/01/18/philippe-mestes-gross-art-project-a-ton-of-sperm/
French artist Philippe Meste wants sperm. His artwork Spermcube is a transparant cube of one square meter, which can contain 1000 liter (or 264 US gal) of sperm.
Meste asks all men all over the world to donate. A donor kit can be requested through the website. You can also become a Spermcube shareholder and make profit from the sales of the Spermcube.