Your boss has just come over to check on your TPS reports and you've had enough of his witty antics. Why not get him with this Squirt Pen and Disappearing Ink? The next time your boss opens his mouth, just "accidentally" press the clicker on the pen to spray blue ink all over his work shirt. After your boss has a hissy fit about it, the blue ink will be gone because it diappears as it dries - brilliant!