189

Use your shop to display replicas of your jewels. The easiest way to not have to worry about shoplifting is to not have anything to steal. Luckily, the MACAW offers an easy solution for this: simply keep all of your wares off-site and show your customers replicas of all of your jewels. Then, when a customer wants to purchase a jewel, you can simply have ...


170

The destructive power of this device would be immense. If you defeated the safeguards on it, it would become the single most powerful bomb ever envisioned. Doing irreversible calculations, as described here, takes energy. It turns out there's a bare-bones minimum amount of energy required to set 1 bit, based on the entropic content of that data and the ...


154

How about hanging birds and mobiles from the ceiling - something that's easily pushed aside by a person when they're in the shop but it removes the spaces that can be easily teleported in to.


111

Supervillains are going to commit huge crimes somewhere. It's what they do. The trick is to predict them, and the easiest way to do that it to bait them. Ft. Knox is well-known and (in theory) highly valuable. It's one of a handful of prime targets in the country that are perfect for supervillainry. If you deprive them of those obvious targets, they'll pick ...


109

But in most stories, FTL doesn't actually follow Newton's 1st law; everybody knows that once your hyperdrive fails, you're dead in the water. Otherwise, the Enterprise could hit warp 9.9 and easily coast across the galaxy. And that actually makes sense in the warp-style of FTL: FTL travel is only possible within the field generated by a functioning FTL ...


94

I know you want proper booby traps, but I doubt they would be the biggest dangers or challenges of invading a military base. Security measures would have a far larger impact. Firstly a 1 meter thick steel door should make it extremely hard to get in. With the electronics degraded and any ball bearings and grease long gone you will literally have to drag ...


93

Tour Ft. Knox, the world's second-biggest distraction (just behind Area-51) You bet there's gold in Ft. Knox! Everybody knows that. Little Johnny down the street knows that! Tibetan monks in Mongolia know that. Your little sister knows that! Every intelligence agency worth a dime has proven it to themselves over and over and over. And it's the biggest ...


83

First thought would be "make an army of lions, bears, tigers, wolves or whatever top predator you have". But that would be wrong. All of them are easily spottable from a distance, and are good targets for arrows and the like. Your key to success is: go small and go large numbers. While you can use small birds to carry on aerial surveys and track enemy ...


74

In two words: absolutely yes. Cryptography, at its core, is not about computers at all. Sure; automated, programmable, electronic computers operating at about a gazillion instructions per millifortnight allow us to perform some pretty neat tricks that would be difficult to pull off otherwise, but there is nothing inherent about cryptography that requires ...


71

Bundt cake pen. Frisky slimes gotta move! If it hits a dead end it will start looking for cracks or go up the wall. But if there is a path of least resistance the slime will take it. It will head off down the pan. Yes, it will circle around, but these are slimes. It will not know it has circled around. It will keep going, moving fast, feeling good, ...


70

1. Space is mostly empty If you pull the trigger on this, you're ruining someone's day, somewhere and sometime Well, not necessarily. There's so much empty space between anything interesting in the universe, that it's very likely that those "shots from a cosmic shotgun" will just keep traveling through the cosmic void, never even approaching anything ...


67

Retractable floor. At night, the shopkeeper presses a small garage door open/close style button that retracts that floor leaving the show cases suspended over a 20 foot deep pit (read as 'your basement') filled with 4 foot deep pool of a tarry slimy substance that's covered in feathers. A few hangings can prevent people from teleporting ontop of the cases ...


66

Plausible deniability for ransom Between abut 800 AD and 1066 AD, Viking raiders terrorized Europe. The raids reached such a pitch that local kings would pay ransom to Viking bands to leave them alone that year. In England, this was called the Danegeld. I can imagine a scenario where politicians, terrified of the supervillains' depredations, pay the ...


62

Animals hire the mercenaries. There is nothing better at fighting humans than other humans. Mercenaries are fighters for hire. Appoint a spokesanimal. This talking crow will visit the mercenaries and arrange terms. The mercenaries will control access to the forest; they are forest guardians. Mercenaries do not really want to grub around for roots and ...


61

As any good locksmith will tell you, any lock anywhere can be fooled. Not all of them can be picked with a bump set, but they can be accessed, one way or another. There's nothing that it would be IMPOSSIBLE to copy. Just more difficult. Let's go about making it more difficult though. First, make the number of planes/requirements higher for the unlock. So ...


59

Just track it Since: Nothing other than foreverium is forever You're a time traveller There's no real reason to worry about this ring, whoever has it right now is as ephemeral as any security system. All you need to do is know where and when the ring is at any given point and you can pick the thing up. Wait until the end of time if you want to and just ...


57

If there is a 10 minute cool-down period, why do you have a security problem? They pop in, grab something, and...busted. Unless they are waiting around for 10 minutes and then popping out with said valuable. In this case the answer is simple - no MACAW devices are allowed in the store. You could probably pay a wizard or witch to cast a MACAW barrier to ...


54

Two-Factor Authentication! Can you broaden your acceptable answer to allow the key to be combined with something else? For example: The lock requires the physical key plus exactly one drop of blood placed on the tip. Perhaps it has to be a female goat's blood or something specific. The lock requires that the key be inserted into the lock at a particular ...


54

Glass jugs Make them big enough to accommodate your slimes; the slime should fill the bottom few inches and most of the jug should be empty space to prevent escapes. A slime that climbs up the wall can't pass the "upside-down" section to get to the entrance. Since it has no bones or structure, it won't be able to hold itself up the wall; so it will just ...


53

The correct answer is to just join the crowd of time travelers getting their own foreverium ring at Evaporation Point. Think about how you've described your foreverium ring for a second. It's immutable, unalterable, and undecay-able. So, what happens when the universe goes old? It survives heat death, it survives particle decay, and it survives at the ...


51

I'm thinking in an entirely different direction. In one of the Indiana Jones movies he met this cult that was dedicated to protecting a relic and keeping unworthy people from getting it. Suppose that, since the apocalypse, the locals have built up a cult that just absolutely does not want anybody to have what's in the military base. They could be the ...


49

Honestly, the humans don't stand a chance. Go the Viet Cong route, various types of pit traps and deadfalls. With a plethora of burrowing and gnawing animals these will be very easy for the forest creatures to make. The big risk is getting caught in them themselves. Of course they can use scent markers the humans will not notice. Even better, burrowing ...


46

In modern democracies, voter fraud is no problem. Actual tampering with the voting process is done by more complex mechanisms that can be done openly. It is all about discouraging people to vote who would vote in a majority against your interest or allowing people to vote who will vote for you. Refer for example to Last Week Tonight on the system in the US ...


46

It's not villains you need fear, it's your own government. And in the modern world you're screwed. There are more cameras watching us than ever before. Heck, if a spy agency realizes where your efforts are concentrated they can simply start spying through everyone's cell phone cameras, etc. and they will end up tracking you down sooner or later (my bet is ...


44

Too many answers with "uncopyable key is impossible" advises, so I have to stand up. There is no need to jump directly to quantum magic to argue and show that to replicate a quantum system one has to measure it and thus destroy superpositions of states which it naturally have and which may be the key by complementing with another quantum system and by ...


40

Guards - The well-paid guards rotate randomly, so they never know which part of the warehouse they will guard when they will be working, or with whom they will work. This prevents a potential thief from working with or bribing a guard. Four guards patrol the exterior walls, while four patrols the interior walls. They have whistles which they use to sound ...


36

If a Macaw is able to precisely aim for a location and determine whether or not the user's dimensions can be accommodated, then it has a targeting sensor. If it has a targeting sensor, technological or magical, then it has a weakness, and someone would discover a way to fool it. Perhaps the device or application fools the sensor into thinking the space is ...


35

The tech you're looking for is Digital Signing. You use public/private key encryption. With this kind of encryption, anything encrypted with the public key can only be decrypted with the private key. You can only decrypt with one and encrypt with the other. You take the document and encrypt it with your private key. Then you attach the encrypted version to ...


34

One time pad is 100% secure against any kind of cryptographic attack we can reasonably conceive, if used properly, and is sufficiently low tech to be used by neolithic technology level (with writing).


34

The zombies will NEVER get over the walls. Why? Physics. Zombies are basically human bodies that are still moving despite being in varying stages of decomposition. Human bodies are mostly water. We do have some skeletal structure, and some of it is very strong, but for the most part, we are bags of water. Now, what happens when you stack up enough people ...


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