I love some of the buttons on my document camera, like the title button that allows me to display the objective on the top tenth of the screen throughout the lesson. I also use the freeze button when teaching math. They do a practice problem; I freeze the image of the problem and also do it. When all are done, I un-freeze the image, and wowie-zowie, there is the solution. The freeze option works especially well for me, a left-hander. I can freeze and un-freeze as I talk the class through a review of homework, showing the answers without my hand getting in the way. Also, my kids love seeing the negative image--they call it night vision!
I joined Quia and devised games for review before state testing. They love playing a Jeopardy-like game, boys vs. girls. I also made some hangman spelling games that they ask to play.
My projector bulb blew after I'd had it about a month. I didn't know how to teach without it anymore! And, believe me, I was a hardcore overhead addict! The 3 days the tech folks took to replace the bulb seemed like 3 months!