A colleague mentioned how nice it would be to have a SMART Board in one of our classrooms for when he teaches philosophical writing, so he could put student papers up and annotate them on screen. But, my oh my, these SMART Boards are expensive. They seem to start at around $1000. I had vague recollections that I once saw that one could do something quite similar with a Wii Remote, and I told my colleague that I was pretty sure I could put together a solution for about $100.
So, I went home and searched the Internet. The Wii remotes have cameras that track infrared points. Johnny Chung Lee wrote free software that works like this: you get a pen with an infrared LED at the tip, point the Wii Remote camera at the screen, calibrate quickly, and then the pen operates the mouse. Simple and cheap, though you still need software for annotating whatever you want. There is also shareware Smoothboard software, for under $30, that is more polished and elaborate, allows using two Wii remotes in case one can't see the pen, and includes software that lets you annotate what's currently on the screen. You don't need a Wii, just a Wii remote, which sells for $33. And you need a Bluetooth adapter if your PC doesn't have one. The infrared pens can be bought for less than $10, and if you use a single Wii remote, the project easily comes in under $100 (you may also need to buy a mounting bracket, or make your own). With two Wii remotes, the project is a little over $100.
We have a Wii and I have a large collection of scrap materials, and that included an infrared LED, an AA battery holder and I had bought a bunch of momentary switches for a now-abandoned project (from Tayda Electronics, in Thailand--surprisingly, their shipping was really cheap, and their components are super cheap), so I quickly made a little infrared pen out of a plastic 35mm film canister, set up our video projector and ran the shareware software. And, yes, it worked. It was a bit fiddly to find positions in the room where the Wii remotes' cameras could see all of the screen, and the film canister often obscured the LED. But it worked.
Harbor Freight helping hands, and it turns out I didn't need to use a second Wii remote. It works nicely, except when the kids are using the other remote with the Wii as the Wii grabs the remote when I turn it on.
I was hoping the kids would enjoy it. With the free driver software (which, granted, is not as polished and much more crashy than the shareware version--but I am cheap), it makes a great controller for Crayon Physics (you need to put Crayon Physics in a double-click erase mode) and works well with the kids' favorite Tux Paint as acceptable with World of Goo. But surprisingly my daughter prefers the mouse.
I had a lot of fun with the project over the weekend. I am not sure my own teaching would benefit from the setup. I don't use Powerpoint very often, and when I do, I don't think I need to annotate on screen. And if I did, I wouldn't mind doing it with a keyboard and mouse.
Basically, the whole thing is a modern take on a light pen, except that the light pen technology was tied to CRT displays.