Here are a few interesting sources I've come across on the web that raise questions of authenticity, ethos, audience, etc. I haven't bothered to make them into assignments because my own class has a different focus, but I figured people might find them useful.

The first one is a pheromone cologne called Pherlure that claims to be the only university-tested product of its kind. It's designed to increase attention from the opposite sex (I think specifically females). If you google Pherlure you can easily find the product page, which includes a link to an abstract of a study supposedly done by the University of Chicago proving its claims. There's pretty good evidence that that site is itself fake, created by the manufacturers of Pherlure. You can see a summary of that evidence here: http://www.di-dehydroepiandrosterone.info/

Here's a column from a recent World Net Daily titled “Soy is Making Kids Gay.” The headline isn't a joke - that's actually the argument the guy is making. I think it’s hilarious, but it's also really creepy and would make a good exercise for a 306 class. You could use it to talk about ethos and logos. In particular, this guy’s ability to make his claim that soy milk is medically indistinguishable from birth control pills look scientific is pretty remarkable. I’m still waiting for the punchline about eating Irish babies, though.

http://www.wnd.com/news/article.asp?ARTICLE_ID=53327