Whatever you have, the free, multi-platform student response system, Socrative.com will use any of these. Did you spend $3000 on Activotes or other student “clicker” systems? Well, you could have simply used those laptop carts, those iPads, a desktop computer, or asked your students to bring their own device and fired up Socrative.
This seems pretty compelling. Right now it’s invite-only, but I signed up. If I get through, I’ll take a look and report back. Click through for a preview in the meantime.