green lightning

[IBM] n. 1. Apparently random flashing streaks on the face of 3278-9 terminals while a new symbol set is being downloaded. This hardware bug was left deliberately unfixed, as some genius within IBM suggested it would let the user know that `something is happening'. That, it certainly does. Later microprocessor-driven IBM color graphics displays were actually *programmed* to produce green lightning! 2. [proposed] Any bug perverted into an alleged feature by adroit rationalization or marketing. "Motorola calls the CISC cruft in the 88000 architecture `compatibility logic', but I call it green lightning". See also feature.