Have you ever used the quizdom audience response system. They are great. Here are a couple of things that they could do to improve they system.

• Add a + symbol so that you can enter equations for the fill in/completion question types.
• Increase the size of the fill in option beyond 10 characters.
• Add the advertized feature of displaying the graph on the teacher's remote.
• Add the a feature where the student's name will show up on the teacher's remote when they have a question.
• Improve the slide editor. There are times when it seems to have a mind of it's own and it isn't very flexible.

Other than that it is the best system that I have seen out there.