The Science Museum in London since 2007 has had an exhibit called "DO NOT TOUCH". A large pole with a barred-off bare metal waist is surrounded by brain-searing yellow warning signs, proximity-sensor klaxons, and screens telling patrons that the pole will give them an electric shock. You can't help but touch it! Yes, you do get an electric shock.
This Place is Not a Place of Honor: The US Department of Energy is designing monuments that warn future visitors away from nuclear waste disposal sites such as Yucca Mountain and the Waste Isolation Pilot Plant. The ideas they've come up with are fascinating — but not one of them has managed to avert the site being Schmuck Bait of the highest caliber. To their credit, they're well aware that anything they design is potential Schmuck Bait, and they're actively working to minimize the bait factor.
Jerry Pournelle once suggested an elegant solution: Put the waste in one of the areas of desert that are already radioactive because nuclear weapons were tested there. Surround it with miles of fence and lots of signs that say IF YOU CROSS THIS FENCE YOU WILL DIE. Some people will do it anyway. "Think of it as evolution in action. Average human intelligence goes up by a fraction of a percent."
Any Wet Paint sign.
Tell a man there are 978,301,246,569,987 stars in the sky, and he will believe you. Show him a "Wet Paint" sign, and he will check and get his finger stained. — Julian Tuwim
There is a similar joke about resturaunt patrons touching hot plates 'just to be sure.'
Apparently, some tech departments will periodically send out emails supposedly with viruses attached, informing everyone at large not to open attachments like that. If someone does, it will turn out that the "virus" is actually a tracer that lets the department tell managers which of their employees cannot follow directions.
Turning off the Electronic Stability Control (either to get a quicker start-speed by turning off the Launch Control or to facilitate street race "drifting") on a Nissan GT-R will void the warranty, should the car get damaged in that mode. Sure, the ESC is shown to make crashes 35% less likely, and there are few legit reasons to turn it off, unless you are stuck in mud or snow... but a button that, when pressed, will let you go 0 to 65 in 3.4 seconds is preeeeety tempting. The 2012 Nissan GT-R would remove the bait, by adding the "R-Mode Start" option, where the ESC may be switched to an "R" mode, only coming on after the initial burst of speed.
Including Schmuck Bait options in multiple-choice questions is common practice for the SATs, standardized tests, and regular school tests. It's so common that test-prep courses actually give the Schmuck a name (e.g. "Joe Bloggs") and demonstrate how this gullible strawman, thinking he's being clever, always falls for the Schmuck Bait.
British revision site BBC Bitesize loves this "trick":
In order to deal with a rapidly increasing population, the Chinese government introduced... a) The One-child policy b) The Two-child policy c) Free Contraception d) The Child Catcher
The Voltage Switch on the back of computer PSUs. Flicking it causes a loud bang, a lot of smoke, and a broken PSU.
rm -rf / for novice Unix users. Especially don't run it as root. rm is "remove". The -r is "recursive". -f means "don't ask me if I'm sure." The single slash denotes the entire filesystem, kinda like C:\ for a Windows machine, but even more. If you run it as a regular user, it'll delete everything you have access to. If you run it as the superuser, (root, user 1, the administrative user) then it'll delete everything. At which point the computer will stop working. Most modern Unix variants will prevent you from running it, since it has no legitimate use.note If you want to wipe the disk and reinstall, then you'll use fdisk or dd. If you want to delete everything because the feds are knocking, then you use a secure deletion tool like GNU shred, rather than something that just marks blocks as dirty. There is no reason ever to use rm -rf / for anything other than quickly trashing a system.
Man page for hdparm. It is an utility of Linux systems for reconfiguring/testing how the OS interfaces with the hard disk, and optimizing those settings for the hardware installed. All the potentially data-destructing options are thankfully lined in BOLD, ALL CAPS warnings stating they are VERY DANGEROUS, and that you should NOT USE THESE OPTIONS.
Also, if one types fsck to check a disk on a mounted filesystem, Linux will give a dire error message: "WARNING!! The filesystem is mounted. If you continue you ***WILL*** cause ***SEVERE*** filesystem damage." It won't stop someone from doing it, they can press yes anyway.
For Debian-style distributions, attempting to remove an essential package will yield the warning "You are about to do something potentially harmful. To continue type in the phrase 'Yes, do as I say!'". Indeed, the action will not complete without typing the phrase. Copy/pasting the line won't work.
This message has the tendency to appear when a distro switch out one important package for an alternative (say, dumping SysV initscripts for SystemD) during a major distro upgrade under certain conditions. However, in this case, the admin doing the upgrade most likely is already prepared for this and knows what s/he is doing.
Also, people who tell Windows users to delete "System32" because it'll greatly improve performance. Windows usually prevents you from doing this however. If you're on an "Administrator" account, you can access the System32 files just fine, but only after seeing a message saying something like "These files are hidden, and are required for proper operation of your computer." You can "okay" the message, but it doesn't actually stop you...
Lecturers at some Universities to catch students.
Luis von Ahn at Carnegie Mellon sets at least one assignment per year with a Google-bomb phrase in the questions, leading to a website with the answer and the correct solutions, which logged the IP addresses of people who entered the website. As students were told not to use the internet to do such questions (and such phrases did not exist), he would then happily accuse students who visited the website as cheaters.
Samir Siksek is also famous for this at Warwick.
Some Software Engineer teachers bug their sample programs in this way to detect code reverse-engineered from that sample program. For example, a program that takes a random number to generate a result would, on a specific number in the test program (and thus all code derived from that program) return a message that the student had cheated.
Invoked by police all over the US with bait cars, which are set out on the street and "abandoned", while an officer watches from a safe distance. All the car's functions are remote-controlled, allowing the police to shut off the engine and force-lock the doors in order to trap the thief. Oh, and there's a camera hidden in the dashboard, so they have proof that you stole it. Also qualifies as a Honey Trap.
Heart Attack Grill: It's as close to Exactly What It Says on the Tin as it can be. It doesn't grill heart attacks, but it is themed around food which is known to cause them and other health problems. It's themed as a hospital, with the staff being healthy "doctors" and "nurses" who serve to customers as "patients". And the food is named after health problems and surgeries. Two spokespeople have already died at ages 29 and 52, respectively. If you are still willing to eat there knowing all of this...
Pang Juan, a general of Wei in China's Warring States period, came across writing scratched on a tree: however, it was too dark to read. Accordingly, he had a torch lit, revealing the writing to be "Pang Juan dies under this tree". The lighting of the torch was the signal for an ambush, set by Pang's rival Sun Bin,note Descendant of Sun Wu to attack. Pang Juan would commit suicide under that same tree.
In Metro Manila in the Philippines, there is a sign set-up in the middle of a two-lane main thoroughfare which reads (in the vernacular) "Do not cross. Someone has already died here. Use the overpass." This is a warning to all potential jaywalkers to use appropriate overpasses and pedestrian crossings. Guess what most of the Filipinos reading it do next.
Rabbits, despite being oh-so-cute and snuggly, are reportedly prone to kicking forcefully with their (clawed!) hind feet in response to the inevitable attempts at snuggling them.
Similarly, cats. Ultra-cute, fuzzy, and snuggly, but also extremely flexible, pointy at five of their six ends, and notoriously prone to violent mood swings. They often like to cuddle, but don't expect them to remain in that mood for a very long time...
A cat lying on its back exposing its belly - apparently it means the cat trusts you not to touch its belly! Pain ensues..
Bot messages. Especially when they hijack someone you know that has potential to send you links. The only exception are YIM spam bots, as they know that any message exchanged opens door for programs to snatch login data.
Friend: I just found a way to find out if someone blocked you! Click here >> www.amiblocked.com
If you clicked on any of the two above or even tried the links above without taking any safety measure, you are an idiot, deserves to be made fun of and must stay away from internet. FOREVER
In a similar manner, people that send you message or emails that say something like "We need to verify your account/your account information may be compromised. Please enter your account information to secure/verify your account." Nearly every single website or online company will NEVER ask for your personal information, yet people on a daily basis keep giving up their info and have their bank accounts or personal identity stolen as a result.
If anyone ever asks if you if you want a Hertz Donut, the correct answer is no. If you say yes, they'll punch you and say, "Hurts, don't it?"
Shortly after the launch of the Xbox One, an image spread around with instructions that supposedly enables backwards compatibility with Xbox360 games, by going into the developer console and changing the sandbox ID to "freezone.reboot". It actually sends the console into an infinite reset loop, effectively bricking it.
The Jimmy John's sub sandwich food chain have folded paper displays on their tables with a giant QR code that says "WHY WOULD ANYONE SCAN THESE!? (I don't even know what they do.)" Scanning the QR code gives you a message.
The "Bullet Catch" is an infamous feat of stage magic which is virtually never attempted today, as several professional magicians who'd historically made it a part of their repertoire have either killed their assistants doing so, or been killed themselves. Despite its deadly record, or more likely because it's so lethal, it's still a tempting prospect for little-known magicians who want to build up their reputations very fast. (The ones who've already made it big avoid this trick like the plague.)
The last widely publicized time that this trick/stunt was attempted was in 1995 when Penn & Teller decided to try it, with Teller firing the gun for Penn to catch the bullet, complete with a US Air Force officer and a Las Vegas Metro Police officer (the stunt was the grand finale for the 2nd annual "World's Greatest Magic" show on Thanksgiving night. Everything worked flawlessly.
Then again, if there's anyone who could be counted on to know how to do this trick/stunt competently, and to make a point of abiding by that knowledge, it's those two.