Rondo Erase Pen
HOLY SHIT THESE PENS!!!
Rondo Erase is a new pen from the Swedish manufacturer Ballograf with erasable ink. The ink can be erased as many times as you like. The technology is based on friction and the eraser itself is indestructible. The pens are delivered with ink in the same color as the pen barrel.
So how can a ballpoint pen now offer erasable ink?
The ink developed for this pen is heat sensitive, and that means that when heated it disappear. So with the silicone eraser rubbing on the ink it heats up the ink so that it becomes invisible.
The ink on the paper will re-appear if you put the paper you wrote on in the freezer. So now you can write a letter to someone, use a hair dryer to make the ink invisible, and then ask the recipient to put it in the freezer to be able to read what you wrote. MIIIINNNDDD BLOOOOOWWWWNNNN!