Gnat Torkington is continuing to post his series of personal reminisces from geeks about how they got into technology. He's just uploaded a whole bunch of them, written by people like Tim O'Reilly, the R0ml, Guido van Rossom, James Duncan Davidson, and even one by me.
I used to go the Ontario Institute For Studies in Education where my father was getting his teacher's certificate. I was five or six. He'd sit me down at a terminal connected to the school's PDP and set me to playing with Eliza or tinkering in BASIC. I loved typing dirty words into Eliza and having her echo them back.
At home I didn't have a computer, but I did have a CARDIAC cardboard computer simulator from Bell Labs that I *loved* to pieces (literally). I used to make elaborate paper control-panels for mainframes in my bedroom out of construction paper and cover my little desk with them.
By the end of that year, we had an acoustic coupler and a teletype terminal and a roll of brown paper like the paper towels in the bathrooms at my elementary school. I filled many miles of brown paper writing BASIC programs and playing Eliza and Hangman (and looking at the source for each, which was mystifying to my little brain).