This TED presentation by "renaissance mycologist" Paul Stamets about mushrooms is worth 12 minutes of your time:

http://www.youtube.com/watch?v=pXHDoROh2hA

There is a longer video at the site where I learned about this video: http://www.ritholtz.com/blog/2012/04/paul-stamets-on-6-ways-mushrooms-can-save-the-world/