You and a super intelligent snail both get 1 million dollars, and you both become immortal; however, you die if the snail touches you. It always knows where you are and slowly, yet relentlessly, crawls toward you. How long can you survive?

Run from the snail to live as long as you possibly can. As time passes you will lose happiness. With lower happiness you will run slower as you slowly begin to crave the sweet death the snail offers. 

To increase your happiness, do drugs and gamble! (the scariest part of this game is that those are the only two happiness mechanics I could think of...)