Found this game online which ultimately challenges every part of your brain in every way. The game is pretty straight forward: There are 139 levels or so, and to go from one level to another you need to uncover a key word or in some cases a (user name/password). In order to do that you need to find clues, interpret hints properly and put everything together. Out of say 2,000,000 people who attempted, only about 150 people completely the whole thing fair n square.
I encourage you guys not to cheat as it defeats the purpose of playing (Be patient and Strong!). Besides, the creator changes keywords once in a while to catch cheaters (and log/ban IPs). So watch out!!!.
The link to the game is here: http://www.deathball.net/notpron/ This is just to get you guys started: for the first level, you click on the door (Dur!!!!) and for the second level, you replace the word "level2" with "level3" in the URL. The clue is the hand pointing up at the address bar. I hope now you get the idea what kinda of puzzles are in this game.