Almost everyone of us uses their cellphone on a basic level, never knowing what you could actually do with these hi-tech masterpieces. These codes allow you to bring up some hidden possibilities of your phone, which can become quite handy for you.

Sara Nainzadeh built a hidden room behind a bookcase when renovating her apartment that she bought in 2009. There is even a book-switch that activates the bookshelf door.

The owner of this cat found a note attached to her collar after she came back from one of her numerous strolls around the neighborhood. Apparently, she had a secret life her owner had no clue about.
 

Apparently, the original "Super Mario Bros." has way more levels than 32 or so. It has hundreds of them! Those levels are hidden away in every cartridge that is gathering dust in the boxes at our homes. They also weren’t intended to be found as they are “broken” and messed up. For example, there are enemies that have no place within them, like a Goomba underwater…
However, some Nintendo enthusiasts have cracked the process and were able to unlock these hidden levels. Here is how you can do it.
 

If we talk about castles, we would most likely think about Europe. But there's a The Old Montreal Castle in Canada that is called Chateau Vieux Montreal and it's right downtown. If you look at these pics you'll see that it is pretty epic too.

Paper money is actually extremely detailed and contains “microprints” that are not immediately visible to the naked eye.

The US government has a fleet of planes that is used to transport their employees to secret bases around the country and here are some fascinating details about the airline that you definitely won’t know.

Chris Manno is a pilot who decided to give us mere mortals a taste of what he sees everyday outside his cockpit window with this narrated picture story of a trip between Dallas and Seattle.

This guy was trying to fix an electric window when he made this interesting discovery.