Proper answer to "excuse me"

If someone says "excuse me" to get your attention, the response is "I'm sorry, yes?" or something to that effect. If they say "excuse me" because you are in their way, then the response is to move out of the way and say "I'm sorry" or "sorry". And if they are saying "excuse me" in a loud, drawn-out, sarcastic way, the proper response is to tell them the 1980s called and they want their dated pop culture references back.

At least that's what I do.

There's more. Such a versatile phrase!

• "Excuse me?" as a question is a request for a repeat of what was just said.
• "Excuse me!" can also follow audible bodily functions and should be replied to with a polite, "You're excused."
• "Excuse me," may be said by someone getting up to go to the bathroom in a restaurant or by someone needing to suddenly leave or take a cell phone call. A head nod is an appropriate response.

Why? What have you done?

I was taught to say "Certainly" in all cases, followed up by whatever action (or inaction in the case of "unseemly noises") might be appropriate.