What does the expression, "Elvis has left the building" mean?

Question

Likewise, what the heck does it mean when someone says your name and then says, "All day." As in, "Bob Smith, All Day." Thanks...

Answer 1

The Elvis one was a phrase. which became a catch-phrase, that announcers made after Elvis concerts. It was made to inform people that there would be no more curtain-calls as "Elvis had left the building."
Its now used as a catch-cry when a person has left usually with some dramatic or obvious depature.
The "Bob Smith" one is just a smart alec reply to infer that you still are & will be Bob Smith at the end if the day

Answer 2

At a famous Elvis concert...there were about 25 encores and when he didnt come back out again, the crowd kept calling for him to come back onto the stage. The were chanting for about and hour for him to come back, until the announcement came over the loudspeaker "Elvis has left the building" So now, it's used when you want to get across the message, that something is really, truly and definately over.
As for "all day" after giving your name....I'm not sure...but someone once responded to my asking their name...to " well the last I checked it was Bill Smith" I guess that's a bit like :Bill Smith, all day" maybe suggesting they might have a reason to use another name but that on this particular day they'll be Bill Smith all day. Silly.

Answer 3

I have never heard the "all day" one, but I'm pretty sure the "Elvis has left the building" quote is from when he was famous and girls were hounding him...they'd announce he had left the building once the show was over so that people would stop crowding around trying to find him.

Answer 4

heartbreaker is correct....
It's kind of a long story but that's about the gist of it....

Here are the complete details....
http://www.straightdope.com/columns/021227.html