When I was on about my 2nd car I had a watch with a calculator in it. The strap broke and I couldn't replace it, so I fitted it into the ashtray of my car (complete with 1.5V power supply) so I could calculate my gas mileage when I filled up (also my car then didn't have a clock...) I had it beeping on the hour and passengers would say "What's that?" and I'd show them and get funny looks....
@betajet, you need to get a t-shirt printed up with "beyond-geek" written on it :)
My geekiest time period (because sadly it was not restricted to a single moment in time) was as a teenager when I thought it would look supremely fricking awesome if I spray painted a plug gold and wore it around my neck with a power cable, to symbolize my extreme love of electricity/physics. Needless to say, I was that girl in high school with NO friends. lol. oh well!
Mine was a gradual descent into darkness.
When I was in grade school, I discovered my dad's old "CRC handbook of Chemistry and Physics" and started reading it for fun.
When I was in high school, I sold a nice audio amp to a friend so I'd have enough money to to buy an ancient VTVM at a flea market.
And, of course, I've read the Hobbit & LOTR more times than I can count and I read the Silimarillian when it was first published in hard cover. It still bothers me that the movie people put elves at Helm's Deep. They just don't belong (other than Legolas, of course).
Geekiest moment I can remember was about 10 years ago when I was checking my gas mileage with the slide rule I keep in the glove compartment. (Hey, it's a great tool for calculating ratios, and the batteries never wear out :-) My grown daughter watched me do this and told me I was a "beyond-geek", a label I wear with pride.
My parents tell me that when I was about 3 years old they took me to the Botanical Gardens. I wasn't interested in the plants. I was interested in figuring out where the irrigation pipes went. Great practice for tracing nets in multi-layer PCBs :-)
Some of these answers are great -- I live the PICNIC acronym (I'm sure I'll be using that myself before long).
And the guy who answered the "Fix anything with Duct Tape?" question with "I fixed my wife's complaining with duct tape once" (priceless :-)
Also the "Ever solved a Rubik's Cube in under 10 mins?" to which the answer was "No, I only had one hand available at the time as I was driving a car." LOL