I must admit, I didn’t finish this game. I guess I’m not among the smartest people in the world. But with your help, I might progress from the 27th level.
So, enough tension, I present you the game that self-entitles itself THE HARDEST RIDDLE ON THE INTERNET.

The game is a detective game, I’d say, created by David Muennich, a german guy that had a lot of time on his hands and some good programming skills. Basically, you have to find clues in any page that helps you progress to the next page. Sometimes you have to click on something to get you to the next page, sometimes you must type a username and a password somewhere on the page and sometimes you must find clues on how to modify the URL to take you to the next page.
Where should you look for clues?
Well, everywhere: the text, the image, the internet, and even the source code. Yes, the source code of the page.
So good luck, and tell me where did you manage to get!