Lawyers do it in front of the Judge and Jury. Lawyers do it in their briefs. Lawyers do it on a trial basis. Let Your Fingers Do It. Librarians do it by the book.
Librarians do it silently.
Lifeguards do it on the beach. Linguists do it cunningly. Linguists do it with their tongues. Lions do it with pride. Lisp hackers do it in cars.