I typically just turn my phone (currenly a Nokia 5185) to 'silent' mode while in meetings or other do-not-disturb-me situations. If I'm expecting a call, I'll put the phone on the table or desk where I can see it light up if a call comes in and decide whether to excuse myself to answer it. I find it highly annoying and disruptive to be in discussions where peoples cell phones and pagers are going off.