I adore mechanical stuff that looks too complicated to comprehend on the first look, old sewing machines, old typewriters, mechanical calculators, knitting machines, clocks and watches, marble tracks etc. I was abysmal in school math, today I'm collecting old mechanical and electronic calculators and slide rules (and use them & show 'em to the kids at schools) Scales and maps are another obsession. Maybe because we were too poor for mechanical toys like Meccano or better Lego technic when I was a kid? Btw I loved the sesame street episode with the what-happens-next-machine as a very young kid. Then again, my wife says I have mild ADHD or something in that direction, idk.