Pretty freakin' cool!
Link: http://pruned.blogspot.com/2008/02/subterranean-farms-of-tokyo.html
(nabbed from MetaFilter)
Can you imagine a one square kilometer underground farm? In Tokyo, its a reality. Read more about it at the above link. It's an educational project for aspiring farmers in Japan, but it remains more sustainable than most factory farms!
Pretty freakin' cool. I'd love to see this in person. It makes me want to go back to Longwood Gardens.