This is the single greatest invention ever

So here's the thing.

I’m looking at the New York Times website, and I see this article about a cool new pen that has been invented.

If I understand it correctly, it’s a perfectly functional ballpoint pen. You can use it to write on any piece of paper you find. But it only becomes cool if you use special paper that has millions of almost-invisible microdots printed on each sheet. Because, in addition to writing on these sheets of paper like any other writing device, the pen also used the microdots to track the pen’s movement, so that it is able to actually download the handwritten information onto the computer and have handwriting recognition. Plus, you can apparently then do a normal CTRL+F search to find a particular word in your handwritten notes.

It will also record audio as you write – so you can find a particular point or word in your handwritten notes, tap the word on the page, and the pen will play the audio from the time that the words were written – very handy for notes from meetings or presentation, since you can go back and listen to exactly what was said. And you can still record audio if you don’t have any paper handy.

But the thing that pushed this device from “that could be handy” to “this is the single greatest thing ever”? The pen apparently comes with a number of sample programs, including “a music program that prompts you to draw a one-octave piano keyboard, which you can then play by tapping”.

It looks like there are quite a few problems with the pen from the review, but all of these are countered by the fact that you can draw a keyboard by hand and then play it. I can't think of anything cooler than that.