The Moog Modular Synthesizer 3C (1967) was one of Robert Moog's earliest instruments and formed the basis of what was to become the world's largest modular synthesizer 'TONTO'. Created by Malcolm Cecil, 'TONTO' ('The Original New Timbral Orchestra'), it eventually comprised two Moog 3C's as well as many other modules from other manufacturers. 

Another famous user was Rick Wakeman - it was one of the massive modulars seen at his live shows. 

And now available as a delightful mug!