I'm not proud that I stole from the vending machine. I'm proud that I figured out how to steal from it.

Fundamentally, I see no difference between being a 17 year old in a basement figuring out that if you send excessive amounts of data into an unchecked buffer, you can gain control over program flow, and being a 13 year-old kid figuring out that by rocking a machine back and forth, you can cause the front items to rub up against the edge of the rack, effectively sawing the plastic off. What is the difference really? Both are fine if you don't use it in the real world and illegal if you do.

And I don't think it's the same as crawling into an open window. Rather, it's more like lock picking, particularly after they started installing these rock-resistant cages and we had to get creative by using two-man teams (one rocking forward, one rocking back). I believe DefCon has a lock picking session every year.

Rocking a vending machine is so obvious that it does not constitute a "hack".

Yes, to you it might be. To a 13yr old... maybe not so much.

It's also a great way to get a trip to the hospital too.

Destructive security hacking isn't typically celebrated here either. Lock picking isn't destructive. The objection isn't the legality of it, but that you were stealing from a company in a couple of these cases.

I remember with those old vending machines with the circular rings - sometimes they get hung up. Someone buys a packet of chips but it just hangs on, and that someone misses out. Passers-by sees it and they try to get two packet of chips, so they pay for another packet of chips. Of course - now two packets of chips are stuck. Sometimes this can go up to three or four.

What I used to do when I see it is spend a minute looking at it, buy a packet of chip in such a way that all two, three or four packs fall down, then hand out the "free" ones to people watching. :)

Now that vending machine technology has improved, I do not see many of these "opportunities" anymore, but sometimes you see the odd one where the door is jammed and there are several packets of chips behind it. I get out my metal ruler and fix up the door, then pick the packets of chips up.

I was getting chips that aren't "mine", but at the time I really hoped I was doing a public service when I was fiddling with those vending machines... (there's a little show-off element to it. ok, more than a little. :) )

I once released a colleague's stuck soda can by ordering one directly above it so it would hit the stuck one and unstuck it.