An invisible man is here to see you
Nurse: Doctor, there is an invisible man in your waiting room.

Doctor: Tell him I can't see him now. Next.

Airplane Trouble
An airliner was having engine trouble, and the pilot instructed the cabin crew to have the passengers take their seats and get prepared for an emergency landing.

A few minutes later, the pilot asked the flight attendants if everyone was buckled in and ready.

"All set back here, Captain," came the reply, "except one lawyer who is still going around passing out business cards."