Thanks Richard and jib. Maybe I'll have to skip the surprise, though it would be a lot of fun.

But are you pretty sure that folks arriving on UA flights can go through various routes to go down to departures? Now that the various responses have rekindled my memory, it seems that any time I've passed through on UA I've done down the escalator that empties out at the UA transit desk.

I guess another option would be to try to have them paged. Does that seem viable?