Crazy tech ideas have long been good comedy fodder. But what of the fiction that became fact? We've found 10 examples of joke technology that made it into the real world.

1. Invisibility cloak
For decades, fantasy novelists like J K Rowling have written about an invisibility cloak that you wear to conceal your identity – and then sneak around and pull pranks on your friends. Yet, the concept is far from fantasy; Boston College has already shown a technique for bending light around an object using metamaterials. You may also remember that scientists in Japan invented an invisibility cloak that projects the image behind the wearer onto a plastic coat on the front.

2. Wireless power
One of the funniest gags at Think Geek was a wireless extension cord, announced on April Fool's Day a few years ago. The description provided some hints about the joke – warning not to place magnets and pets between the signals. Part of the "in-joke" is that wireless power gags have been around for a while, ever since NASA introduced (in all seriousness) a concept where they would beam power down to earth from orbiting satellite. The reality: such a concept could materialize eventually. Today, companies such as Convenient Power and Wi-Power already have working prototypes where you set your cell phone on a pad to charge it, saving on cable clutter.

Tech jokes that became a reality

3. Unborn baby updates Twitter status
In 2007, CNET posted a fake news item about a baby twittering from the womb. As if to prove that the concept could work, Kickbee invented a stretch-band that women can wear that sends the kick sensations to Twitter, reporting the veracity of the unborn child's tweet.

4. Rodent sightings mash-up in Google Maps
CNET (again) posted a fake story on April 1, 2007, about a Google Maps mash-up for detecting rats, called Ratatattle, in New York restaurants. The post explained that users could see the number and size of the rats, and if they were "anywhere near the food" – a dead give-away. Later that year, the City of New York created a rat indexing system, available as a PDF map, showing neighbourhood rat infestations.

Tech jokes that became a reality

5. 8-bit tie
Think Geek was at it again with their April Fool's Joke about an 8-bit tie. Caving to pressure from Nintendo fanboys, the site actually created the tie, made from fake silk.

Tech jokes that became a reality

6. Paperless toilet
Office automation expert Amy Wohl famously predicted, in 1978, that the paperless office is about as likely as a paperless toilet. In 2006, her joke became reality in Britain when, according to a Daily Mail post, a Japanese restaurant in London demonstrated a paperless toilet, providing a choice between "bidet" (a gentle spray) or "wash" (a more thorough cleansing).

7. Conficker worm
In March of 2008, the world braced for the Conficker worm which, according to rumours at the time, would start spreading on April 1. In reality, this reverse April Fool's joke has spread on many other days of the year before and after the April 1 date, causing millions in damage on every continent.

8. Whistle to find your remote
One of the long-standing jokes about losing the remote control is that, some day, we will be able to whistle to find it. The joke has become an actual product: PrankPlace.com sells the Whistle and Find Remote Control – which is a whistle transmitter and receiver you adhere to a remote.

Tech jokes that became a reality

9. Google announces mail client on April Fool's Day
One of the most confusing jokes from 2004 was actually not a joke at all. After Google's long history of announcing fake concepts on April Fool's Day (such as e-mail you can send back in time), they announced Gmail on April 1, 2004 – causing some users to think it was yet another prank. The reality: Gmail is now one of the most dominant messaging services on the Web.

10. Movies that use surround-smell
The concept of "surround-smell" has been around for a while, usually as a joke concept. A Portugese designer has invented a product called SMELLIT, which includes 118 different smells triggered by events on a DVD. Whether we want to smell action heroes is another debate.

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