TOKYO -- Japanese stationery maker Pilot's Frixion Ball erasable ink pen has come a long way since it debuted about a decade ago, becoming a huge hit with people who, well, make mistakes. But what few realize is that the ink is actually not erasable. It just becomes invisible when heat is applied.
And therein lies the magic of this handy writing implement. Heat from the friction caused by rubbing the pen's hard eraser against the paper results in a chemical reaction, apparently "erasing" writing by rendering it invisible.