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.
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 with viruses attached, informing everyone at large not to open attachments like that. If someone does, a conveniently-attached tracer 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 to such a degree that test-prep courses actually give the Schmuck a name (e.g. "Joe Bloggs") and demonstrate how this gullible strawman always falls for the likely-looking, but wrong, answers.
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.
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.
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.
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.
In the Battle of Leyte Gulf, The Japanese Navy planned for their (decoy) Northern Force to get the attention of the US Navy's covering forces and draw them away so that their Center and Southern Forces could attack the American Landing Zones at Leyte Island. William F. Halsey, commander of the USN 3rd Fleet, fell for the ruse by speeding after them with all of his ships, leaving only a handful of Destroyers and Escort Carriers at the mercy of an attack by Center Force which occurred near Samar Island. The handful of Destroyers and Escort Carriers ended up facing off with the vastly more powerful Center Force and managed to win the day through sheer ballsiness, attacking the larger force with such ferocity that the Japanese commander assumed that Halsey's main force must still be nearby and that Taffy Three was merely delaying to keep Center Force in the kill zone.
Using bait is an essential part of the tactics made by Sun Tzu. As he once said: "All warfare is deception." If you offer the enemy something made of nothing and he is gullible enough to take it, you will be one step closer to victory. The reason why most of the Allied Military Deception Operations have met with success was because of the fact that Adolf Hitler was an absolute sucker for schmuck bait. They would leak fake documents to German intelligence which would then be backed up by false activity and objects which ranged from fake supply dumps to inflatable/wooden vehicles and included fake radio traffic and simulated vehicle noise.
Operation Fortitude South: The allies created a fake army at Dover, made up of inflatable tanks, and put General Patton in command of it to convince the Germans that an invasion would take place at Calais, the region of France that was the closest to the British Isles. As Patton's reputation as an aggressive commander was well-known and feared by the German army, Calais was heavily fortified and reinforced by 15 divisions in preparation for the supposed attack. Even after the Allied landings in Normandy were successful, the Germans were still convinced that an invasion of Calais was going to happen soon. It wasn't until they learned that General Patton and his Third Army were in Normandy that they realized they've been completely fooled.
Actually they never caught on: The double agents who fed them much of the info continued to be believed right up to the end of the war, a couple even receiving medals in the dying days of the Reich. The appearance of units supposedly in FUSAG, as well as Patton, was attributed to the fact that Allied forces were taking a beating, and FUSAG being used as reserves, thus making the Germans think they were winning! It was to be replaced by another British/Canadian Army... which also didn't exist.
Operation Fortitude North: Britain 'simulated' the build up of military forces in Northern England and engaged in political talks with Sweden to fool the Germans that there was going to be an Allied Invasion of Norway. Hitler fell for the scheme by having 13 Divisions stationed in Norway to repel the invasion that never came.
Operation Mincemeat: The British allowed a dead man, by the fabricated name of William Martin, with fake documents attached to him to be found at a beach in Spain by German intelligence. The documents suggested that an Allied invasion would take place at Sardinia, Corsica, or Greece. As a result of Hitler's conviction to the authenticity of the documents, reinforcements and defensive preparations were diverted to those areas instead of to the actual target of the Allies: Sicily. The success of Operation Mincemeat made Hitler and the German Army very suspicious of any documents that they would chance upon later in the war, which affected the outcome of the Normandy Invasion and the initial stages of Operation Market Garden.
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...
Bot messages. Specially 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.