Donno how many of you know abt this but it's one of the best time pass I've come across..
Created by some of IIM-I guys (Indian Institute of Management - Indore) it is simply-too-good..
Second version they released is KlueLess Part 2. Rules are similar but after doing part 1 you would surely be careful enough to read them. :)
The link to the game is inside the rules.