Jamming is a bad idea. I'm responsible enough to leave all of my gadgetalia on vibe, and I think others should definitely do the same when in public places. Yes, I'd be furious if somebody's cell phone ruined a great piece of classical music. But we shouldn't attack the technology - we should, as a society, change our cretinous behavior.

Most of my colleagues now use a two-way pager for business commo. That way, you can respond "I'm at lunch with a client...will call you in an hour" without disturbing a soul. Not to say that 2-ways pagers can't be abused too - I'd hate to eat lunch with someone who spent the whole hour tapping away at the little keys - but they are a vast improvement over a cell phone in specific situations. Most two-way pagers also have an option to silence the key-clicks, making them completely silent.

I also like the silent car on the train and silent rooms in restaurants. Those are a great idea...I just don't like the idea of jamming.

Side topic: Anyone here ever wonder whether casinos jam cellular signals? I noticed that my phone and pager both immediately become useless upon setting foot in any of the large Las Vegas casinos. Maybe they build those huge buildings out of lead or something...