You might think what are these used for? So, it is just for your fun.
Some interesting hacks for Google are listed here.
This one is my favorite and most interesting. You just have to search "Thanos" in your Google Chrome browser and click on the "Thanos Glove" on the right side in biography and see the magic.
This is very amazing trick. Search "Google Sphere" and press I'm feeling lucky. Then see what happens next.
This is also very interesting and hidden magic trick of google. "Friends is a popular American sitcom series. You just have to search any character of this series with the keyword "friends"; on right side in the biography section click on the icon with the title and see the magic. For example: Search "Monica Friends", or "Ross Friends", or "Joey Friends", "Phoebe friends" and so on. Enjoy!
ElgooG is a website which interfaces like google mirror and it contains more google tricks in it. You can visit this site to learn more hidden google tricks.
Some more tricks!
To learn more tricks and how to execute them watch this amazing video and become an online magician.