GoSoapBox - Polling, Quizzing and Class Barometer

GoSoapBox is a website that offers a few key services for classroom teachers to use to gather information from students.  You can use it free with 30 students at a time, but must pay more if you had a larger audience.  The key parts, they call them events, include:

• instant polling
• online quizzing
• discussions
• real-time classroom barometer (confusion meter)

There are a bunch of sites that do the first three but the fourth one was most intriguing to me.  Basically, students visit the site and and login with a unique code.  Once they're in they see whatever events you have set up for them and at the very top they see the Confusion Barometer, which is a switch to toggle between "I get it" and "I don't get it".  What shows up on the teacher's screen is the number of students on each side of the equation.