It is sad that most sushi lovers will never have real wasabi. I had assumed that I had sampled real wasabi when I spent several days eating sushi morning noon and night in Actual Japan. But even then, there is a good chance I never tasted the stuff. The reason that most "wasabi" is fake, and the agronomy and chemistry of wasabi, turn out to be really interesting. Here is the background info references in the video.
This was posted by our good friends over at cracked.com. (Actually, I think they are good friends of mine...old college buddies from my days as a lovable scamp at Gtown!) Anyway, worth a read. (Disclaimer: do not read if you have a weak stomach) 6 Most Terrifying Foods in the World