Been using the name for a long time, from when I originally went online back in 1990.
It's from the C.S. Lewis space trilogy -- "Out of the Silent Planet," "Parelandra," and "That Hideous Strength" are the titles in it. The main character's name is Ransom. I admire the character, and I've long enjoyed C.S. Lewis's works.
(Unfortunately, that silly Mel Gibson movie came along much later and ruined the name for a time!)