You Windows users don't have to worry about pasting pictures into Paint anymore! Gadwin PrintScreen changes the PrintScreen key so that it saves the screenshot as soon as you press the key! It's also highly customizable!
http://www.gadwin.com/printscreen/
Just follow the link in the first paragraph, scroll to the bottom, and there is the download for no charge at all!
NOTE: DO NOT DOWNLOAD THE PROFESSIONAL VERSION, UNLESS YOU WANT AN UGLY "UNREGISTERED VERSION" SPLATTED ONTO YOUR SCREENSHOTS!