I used to be a phone phreak in my younger days back when the blue box (for
free long distance called) used to work.
The coin sounds in a payphone is called a red box. Doesn't work on COCOT
(customer owned) payphones because the dialtone you hear is not from Ma
Bell's line but generated by the phone.
A young entrepreneur named Steve Jobs and a friend started out manufacturing
blue boxes as a garage enterprise. After they accumulated some capital,
they decided to go legitimate, and switched to producing a very crude and
primitive (by today's standards) computer. That product is what got the
personal computer revolution started. They named their company APPLE
COMPUTER.
