I agree with Natalie and Ila. If you get a message in your email about "cheap" Viagra and other pills of that nature, then delete it! Cheap more than likely means fake, and who knows what the hell they would send you. It could be horse tranquilizers for all you know!
The internet offers them a lot of anonymity, so they aren't too worried if you got sick(or worse) from their "products". All they want is the money.