Leapfrog has one called the Fly Fusion pen. It's made for kids, but the new one doesn't look so much like a toy. It doesn't do the sound recording. BTW, the guy who developed the pen for Leap Frog left the company (on amicable terms) to found LiveScribe, maker of this new Pulse pen.
It's definitely the sound recording that has me sold on this. I never took a laptop to class in undergrad, but everyone in law school does. Most law schools require laptops (mine doesn't). So I've got in the habit, as everyone does, of opening my laptop at the beginning of class and taking notes on it. It's awful. My notes are way too good. I type right around 90 WPM, and I swear to god, info enters my ears, stopping only for the briefest of moments in my brain, and then exits my fingers. I swear I'm being trained to be a scrivener more than I am a lawyer. I end up at the end of the semester with 300 pages of notes, that are virtual transcriptions of the lectures. But what am I going to do with that many notes? I can't go through all of that? And in the process I'm wasting the class lectures transcribing rather than actually thinking about the lecture. This pen seems like a much better way.
I've known about the Logitech pen for years, and that doesn't interest me at all. If it's just a matter of computerizing my notes, a laptop is better. I can type a helluva lot faster than I can write. And my laptop already is a tablet. That's practically useless. It's the synchronization of your notes with the audio recording of the lecture that makes this thing great.
As for the calculator watch (and Shardian, I'm sorry, but it does NOT look sharp

), this does one better. Write an equation on your paper and the answer will appear automatically on the screen. Need a translation? Write a word on the paper and get the translation on the screen, and spoken through the speaker. Kinda cool.