Filbo is just a boring D&D handle. It must have been around 8th grade when I created the character, a magic-user named Filbo the Fantastik. He actually gained a lot of levels really quickly because we were using a TSR Games premade scenario, and there was a cache of ridiculously valuable equipment that we got lots of experience for looting. He also had fairly high levels of psychic power, not that it ever did him any good. The original Filbo character never died, I just stopped playing D&D. I might even have the character sheet somewhere.

Later, during my Apple II game cracker days, I was "Filbo of the BackSide", "the BackSide" being me and my cracker buddies who had observed that for whatever reason, all the best games ended up on the back sides of our holepunch-modified "flippies".