I'm going to start off with what I think is a pretty cool device. I have actually used this and I was initially a little disappointed in the noise I see when used with modeling lights. But, after a while I got used to the noise and didn't notice it any more.
Zigview attaches to the eyepiece of most any digital or film SLR and displays the image in real time on a 2.5 inch color display. It also has an additional output that will allow it to be viewed on any video monitor. The Display flips around and up and down for easy viewing, without bending over to look through the display. It can also be detached and viewed away from the camera.
Here is a list of camera Models that the Zigview will fit to:
I feel this would be perfect for school photographers as it will better able the photographer to frame and crop the students without having to bend over and look through the viewfinder each time. Much like in the days of long roll cameras such as the Camerz Classics, ZII, & ZIII. You can also just tape a camera mask on the screen for verifying head size and crop. This will save a lot of time in ImageMatch doing head-sizing. You won't have to send your camera in to have the viewing screen etched.
You can purchase the Zigview finders online at most of the big camera stores. It appears to be going right now for $399.00 at B&H Photo. The previous generation, which doesn't swivel or detach is going for about $279.00 online.