Like sushi?  Well, you might have been conned the last time you were eating it.  This article from the Wall Street Journal (http://online.wsj.com/article/SB125988474375175571.html) talks about how researches recently discovered that fish ordered from menus in New York and Denver were sometimes a cheaper version of the fish or an endangered species.

If you think about it, eating at any restaurant is a matter of trust.  We trust that the ingredients are correct and cooked correctly.  This leads to a broader problem of a concept called traceability.  We want to know where our food is coming from, and what species it is.  And if it is incorrect, we as a consumer are pretty much screwed over.

As the end of the article mentions, it would be cool if we had an iPhone app that just scanned the sushi to see if it is the correct species.