Here's a handy tip for anyone who gets spam snailmail. When sorting your mail simply look at the indicia (post mark in the upper-right). If it says "First Class" examine the mail piece further. If it says "STD" or "Standard" you can safely pitch it without further review. Standard Mail has an average non-delivery rate of about 6% and is inexpensive to send. As such, a mailer will NEVER send you something even mildly important via Standard Mail. First Class is almost always delivered, much more expensive, and mailers use it to send you something you need to see. A real time-saver.