I just got an email from "Admin" stating that my email (Yahoo) had exceeded it's quota and will be suspended. To avoid suspension, I had to click a box that stated "Contact Yahoo Service". It was politely signed "The Admin Team".
I checked the address of the sender at it was from a Hotmail account. Deleted without remorse.
Be sure to check who the sender is on your emails before clicking on the links, and never give out your password.