Using both the CTRL and META keys. "The command to burn all LEDs is double bucky F."
This term originated on the Stanford extended-ASCII keyboard, and was later taken up by users of the space-cadet keyboard at MIT. A typical MIT comment was that the Stanford bucky bits (control and meta shifting keys) were nice, but there weren't enough of them; you could type only 512 different characters on a Stanford keyboard. An obvious way to address this was simply to add more shifting keys, and this was eventually done; but a keyboard with that many shifting keys is hard on touch-typists, who don't like to move their hands away from the home position on the keyboard. It was half-seriously suggested that the extra shifting keys be implemented as pedals; typing on such a keyboard would be very much like playing a full pipe organ. This idea is mentioned in a parody of a very fine song by Jeffrey Moss called "Rubber Duckie", which was published in "The Sesame Street Songbook" (Simon and Schuster 1971, ISBN 0-671-21036-X). These lyrics were written on May 27, 1978, in celebration of the Stanford keyboard:
Double Bucky Double bucky, you're the one! You make my keyboard lots of fun. Double bucky, an additional bit or two: (Vo-vo-de-o!) Control and meta, side by side, Augmented ASCII, nine bits wide! Double bucky! Half a thousand glyphs, plus a few! Oh, I sure wish that I Had a couple of Bits more! Perhaps a Set of pedals to Make the number of Bits four: Double double bucky! Double bucky, left and right OR'd together, outta sight! Double bucky, I'd like a whole word of Double bucky, I'm happy I heard of Double bucky, I'd like a whole word of you! - The Great Quux(With apologies to Jeffrey Moss. This, by the way, is an excellent example of computer filk --- ESR).