I loved this pen so much that...
(1) I bought several packs of them before I left Japan.
(2) I gave them as a gift for my labmate as his souvenir
(3) When I attended a Tech fair and could choose between a number of cheap gifts, I chose this pen over the free computer keyboard they were handing out. Ponta was shocked, "You want that pen when you could have a free keyboard?" I smiled back. "Yes! Besides, what would I do with a Japanese keyboard? I don't need any more luggage to haul back to the US."
I had no idea if they sold them in the US but I wasn't taking any chances.
Turns out they do sell them here but the Japanese design is better (of course it is). However, I also found out from my internet searching that the pen uses a new type of ink technology that fades with friction.
The moment I gave one of the US versions of the pens to my labmate and told him about the ink technology, he started laughing, "Oh man, now I just want to see what will happen if we put a heat gun to this."
We work in a lab that happen to have heat guns so we sprinted downstairs to try it out. It's true! Disappearing ink!
It's like an awesome spy gadget.
Except, you can still see what you wrote, even after it's disappeared.
And what spy carries a heat gun around them to destroy the evidence?
Wouldn't burning the evidence be just as effective?
Yeah, so no worries about spies trying to buy out all my pens.
Now, I just have to remember not to leave anything I've written out in the summer heat...ever.
Now you see it.
Now you don't.