Toss me a mike...
I think CatchBox is a great idea! A soft, chuckable microphone that you can throw to an audience member who wants to ask a question.
It's like a conch, but less fragile, which is also good for maintaining civilised discussions...
Thanks to Adrian Higgs for the link.

Comments
Actually, for a good radio mic with a receiver, I'm not sure that's too bad... assuming it is a good mic...