Gel ink pens, highlighters and now markers are part of Pilot Japan's amazing FriXion line. These erasable markers write in vibrant colors yet erase wonderfully through heat created from friction. Just rub the rubber end over the ink to make it transparent, and you can write on the same area again and again!
Interestingly enough, the ink in these pens will actually reappear when the temperature reaches below -10 C (under 14 Fahrenheit). A freezer is sufficiently cold enough to make the ink start to reappear, you can watch a video on how it works here. It is like a magic pen for adults!
Because the ink in this pen is thermo sensitive, we do not advise for it to be left in hot cars, used for mailing, or subjected to a condition that exposes it to a lot of friction.