I've recently been hooked by this game after being introduced to it by Rabbit. She's a bad influence.
Now I'm like crazy about this game. Basically it's kind of like an investment game. You start off with around 8M dollars then try your utmost best to make yourself as rich as possible ie to become a millionaire, centurian, billionaire etc. At the moment I have 7 billion ++ in my hand but it's not enough. I wanna be richer... If only the money were real. 
I even have this tracker thingy to see which investments are going up or down. I know, I'm beyond help.
But I'm not lying, try it yourself, and see whether you get hooked or not? 