Hmmm... thanks. It would be useful for testing the hardware.
But I was thinking on real applications, like painting software, etc..
I have a Trojan lightpen, it just takes over from the mouse. It works with all programs that support the mouse. All paint and 3d packages support it. It's quite precise, has two buttons on it. But it gets tiring quickly. I ended up getting a Tabby graphics tablet, and then a wacom. Outline sketching with the lightpen are still cool though, then I switch to the tablet for the rest.
It uses the tv phosphors to draw. It won't work on black areas of the screen (at least mine won't). You will need to turn the brightness up, so that black areas are a dark grey. I don't think it will work on an LCD.
