A bunch of machines in an IT suite that I was revamping for a school, all tied together with serious steel cables, attached to the machines with some quite serious adhesive on a plate secured direct to the metal chassis of the machines.
Because they were all interlinked, and the cables padlocked together, you couldn't steal one without the one next to it, and so on. I thought it was going to be a nightmare of having to reimage them all in-situ or going through a bundle of different padlocks key endlessly to separate them, but I thought I'd give things a shot to see if there was an easier way.
I knew that you couldn't just pull the computers apart by brute force - I'd witnessed one fall to the floor hard and just dangle there by the plate/cable, and seen a few cursory demonstrations by big strong men trying to pull on them.
But every system has a weakness. In this case, the hefty metal plate that was epoxied in some manner to the chassis that everyone assumed was inseperable. Like with a maglock, it's not how strong it attaches when you pull laterally against the lock, it's how you can break that lateral surface area connection.
Turns out, a small flatblade screwdriver inserted into a tiny sliver of a gap between the chassis and plate, and then a small "twist" rotation of the head at normal hand strength would easily separate the two surfaces. Despite the fact that you could probably tie the offending articles to two vehicles driving in opposite directions and only ever snap the cables not the attachment, once you got the hang of it, you could literally walk down the row, stab, twist, stab, twist and fire the plates off the machines at high speed with nothing more than a basic hand tool and hand-tight motion. And no damage to the machines.
Headmaster of the school came past about 20 minutes after he'd said he'd go get me the keys, saw the pile of hefty steel cables and plates on the floor and his now "insecure" IT Suite and was flabbergasted. We never bothered to put them back on. (And, yes, I had permission to remove them if I could, before you ask).
If I found it, you can be sure anyone determined to steal those machines knew it too, even if they hadn't brought bolt-cutters.
Similarly, schools all used to just buy expensive projectors and dangle them from their high-ceilings on long-rods. In time, people became aware of the necessity of a "swing test". Literally, if you can't swing from the rod with your full weight then it only takes seconds to get the projector down and walk off with it. Sure, you'll damage the hell out of the ceilings/joists, but burglars tend not to care if they can walk out with £1000 of kit in ten seconds.
Despite then being told by several places that "our projectors have to survive a swing test", never did find anyone who even suggested it was possible to build or fit such an item if you're just attached to joists and your ceilings are 14 foot height, so the pole has to be at least 8 feet long. They learned quickly that leverage and brute-force beats ingenuity every time. After that, they started to buy projectors that were marked educational use only (destroying resale value on the main markets), had passcodes to stop them turning on, that weren't as valuable, or that mounted "short-throw" so at least the thieves only damaged a £50 bracket rather than created a £1000 ceiling repair for their insurers.