With this app you can have an audience vote on things, or ask for their opinions as short tweet-sized answers. It was very easy to use, but you need to use the PollEverywhere.com site to edit the questions after making them. It's a slight annoyance, but pretty easy.
The product is free for the first 40 responses to any question. That's good enough to take a decent sample of opinions, and more than enough for discussion generators.
So far I've played with the following:
- pre-tests to measure where the room's knowledge is at
- live word clouds from my audience's thoughts
- running contests where the audience submit the ideas, then votes
I *really* like how this distracts my audience from being distracted by web/email.