I've always wanted to build a spring loaded 30cm titanium spike that would shoot from the seat pole through the seat if not disarmed. Obviously completely illegal, but a satisfying mental exercise.
When I was in college, like many struggling students, I didn't have much money, my means of transportation was a 3 speed Stermy-Archer 3 speed bike that had the best security system ever, I never locked it. It had something wrong with the 3 speed and if you stood up on the pedals it would slip and the rider would end up with their taint on the center bar, ouch. It was fine if you were not in a hurry and took your time. There were a number of times when I came out of class and would find it laying on the ground about 30 feet from where I had parked it.
The classic reason for that fault in an old 3-speed SA is minor misadjustment of the gear change cable. The gear lever basically pulls a chain further and further out of the hub, going from 3 at minimum pull to 2 to 1. Unfortunately there's a "neutral" between 3 and 2, so the cable needs to be carefully adjusted so that the 3/2/1 positions of the lever give you all three gears and avoid the neutral section. This design defect was apparently rectified in later versions of the 3-speed hub at some point after SA were bought by Sun Race.
Still, I wouldn't personally ever stand up to pedal on an SA 3-speed unless I personally owned it and knew its maintenance condition...
You must have had a nice grin seeing that. I also read reverse psychology tricks on biking boards such as not locking the bike, which convey a sense that the owner is not far / in sight and scare most robbers. Requires balls.
OK, one more of my dopey stories.. I live on the shores of Lake Washington and some years back (when I was a lot younger) I was into wind surfing and I had a pretty nice rig. I was moving to a new place and I had long since drifted away from the hobby of wind surfing to I list my board and rig to sell, but I didn't get any responses so for a fun experiment I carried it across the street and rigged it up and just left it there and went back to my place and sat back to see how long before someone would steal it. It was there for a day and a half and a nice young man called and said he wanted to buy it. He seemed nice so I told him where it was and that he could just go get it and it would be his for free (he could barely believe it). About 30 minutes later I saw a young guy packing it up and taking it away. I felt kinda good about it I guess, hoping he would have fun with it. A few hours later he called sounding very anxious and apparently his parents did not believe the story. So I told them to come by, which they did. His father insisted that they pay me something for it, I relented and told them I would give the money to charity. Sometimes something like that happens, and it just renews your faith in people.
Maybe. Except for the "brought in for questioning by police, bike impounded, paying for a lawyer, etc" parts :(
I must say, however, that after my new (expensive, and lovingly customized and maintained) bike was stolen, I did fantasize about remote-controlled explosives. But then I just filed an insurance claim, and replaced it ;)