Now, lets avoid making value-based judgements regarding the morality of it. Sure, it's illegal. However, it seems that it generally passes through customs unnoticed if you buy a reasonable amount. In all honesty, I've never done it, but as someone who lacks health insurance, I'd benefit from refills (contact lenses, medications) without continuous out-of-pocket checkups. That's no excuse to do something illegal, of course.
Interestingly, there's this drug called Stablon that's supposed to be extremely effective as a mood enhancer, but is not approved in the US. It has very few side-effects in comparison to SSRIs and works immediately. It's one of the more popular drugs people buy online overseas. I understand that you run the risk of getting a fake or third-party product which could be dangerous.
Anyone order any prescription related thing online without a prescription?