Guess Which Billionaire This Backpack Kid Turned Into!

Before this beanie boy turned into a billionaire, he was just backpackin' around around town, kickin' the soccer ball and swimmin' up a storm in Seattle ... and playing with computer systems when he was just a teen.

This guy's definitely got the brains ... He racked in a near perfect score on the SATs, and he dropped out of Harvard, because he was just too dang smart! He has a Porsche car collection, and at 69 years old ... he's still workin and loves playing pickleball and tennis.

Need one more clue? He's a grandpa!