My first VK2 call was VK2IDS … In Deep S**t 
Which was quite appropriate for the time.
Now I’m VK2IB, which doesn’t have any particular meaning, it was just the first available 2-letter callsign when I got the chance to grab one.
My UK call is GM4LGK (that doesn’t mean anything either) and I completely agree with Phil G4OBK, the final “K” can be a pain in the proverbial under pile-up conditions when signals are weak.
73
Bernard VK2IB