During my primary school days i was known as "bobby" mainly because it was cool for others to say "bob a job", this originates from my hatching days (spending the majority of time of a football game, in the opponents box) stealing goals.
its short for robert...thats cool no?
A natural progression to robby occured at secondary school, joining other mates sully, foxy, danny, richie and cozzy. somewhere along the path me and richie got into Stargate, and proceeded to use somewhat satirical names online (and joking about) of rickophis and robnubis...yah "NERDS!". So my choice for username was either robnubis or robby, i made the logical choice.