List of boxes

Blue box	Tone generator, emitted 2600Hz tone to disconnect a long-distance call while retaining control of a trunk, then generated multi-frequency tones to make another toll call which was not detected properly by billing equipment. Obsolete as it relied on use of in-band signalling of the no longer used Signaling System 5.
Black box	A resistor bypassed with a capacitor and placed in series with the line to limit DC current on received calls. On some mechanical relay switching systems, separate relays were used to stop ringing on an inbound call and to start billing timers. The black box was intended to trip one but not both relays, allowing ringing to stop but not showing the call as answered for billing purposes. Obsolete with the replacement of mechanical relay exchanges by electronic switching systems.
Red box	Tone generator, emitted an Automated Coin Toll Service tone pair (1700Hz and 2200Hz) to signal coins dropping into a payphone. Obsolete.
Green box	Tone generator, emits 'coin accept', 'coin return' and 'ringback' tones at the remote end of an Automated Coin Toll Service payphone call. Obsolete as these tones controlled phones designed to rely on manual operator assistance for coin-paid long distance calls.
Clear box	Microphone and amplifier, coupled inductively to payphones where the handset microphone (and just the microphone) was disabled until a coin was inserted. An "opaque box" was a variant which also included a keypad. Obsolete as specific to a rarely used post-paid coin phone design which is no longer deployed.
Violet box	A resistor (several hundred ohms) which could be clipped directly across the line to make it appear off-hook or in use.
Gold box	Diverter. Calls received on one line are forwarded elsewhere using a second telephone line.
Beige box	Telephone installer's test handset; a standard telephone set on which the plug has been replaced with a pair of alligator clips.
White box	In Australia there was a software program based on the commodore Amiga 500 personal computer called White box which was used for phreaking, it used CCITT#5- (R2) tones to manipulate the phone systems in Australia in a similar way to blue boxing. In other countries white box can be referred to a Portable DTMFtone-dial keypad with speaker which was used to access an answering machine to hear your messages when you were away from home and also could be used on PBX phone systems that required tone dialing & used to generate tones if the telephone is rotary-dial or its keypad is locked.
Silver box	Tone-dial keypad with four extra buttons (A, B, C, D) formerly used to indicate priority on military autovon calls. This sixteen-key tone keypad is factory-installed on many amateur radio rigs for controlling repeaters but the extra keys are rarely used.
Magenta box	AC ringing current generator, connected directly to a telephone to make that phone ring.
Orange box	Caller ID frequency-shift keying generator, connected directly to a telephone to send CID. The combination of a magenta box and an orange box is a vermilion box.