It comes from an old spanish TV programme that finished in 2000 I think. It was like the news, but it was a humor programme. They made fun of everything and they had a section where they made fun of some reality shows participants. One of them was Chenoa (strange name) and they predicted her future once and once and once again. Every single time they named her son with a strange name (like the mother) and one of those was Garrabutártulo.
And that's the story of my nick :p
Believe it or not, when I was about to make my msn account, it was already picked :s