i worked in an area a while back where there was a lot of radio communications. a bunch of engineers had "call signs" we always joked that these guys had call signs like "Zeus", "Loads", "Candle" and so forth. i had to do some radio system checks for some regression testing with several people within a 150mile radius. on one of the radio checks i was asked to provide my call sign. being the smartA$$ engineer i was at the time i used one of the CB handles from convoy. Little did i know that was a heavily monitored channel.
during this rather large meeting with over 100 engineers, pilots, support people and such. the chief engineer ask about the radio system communication checks. he then paused and asked "who the hell is this rubberduck guy". Being a young engineer hiding in the corner i sheepishly raised my hand and say "that would be me sir". He proceeded to say "Well hell rubberduck you wanna tell me how those damn radio checks went or not". My response "5 by 5 sir, 5 by 5"
that name has just stuck for 15 something years now.