After Facebook's initial public offering paper revealed that Zynga accounts for 12 percent of the social network's revenue, ZNGA has been on quite a bull run up at NASDAQ. After hovering around $10 per share since its own IPO in December, Zynga's stock graph takes a hockey stick-shaped turn the moment markets opened after Facebook's S-1 filing hit the Web. It kept running up and up until lunchtime on Friday when the stock price peaked at $14.35. Without using a calculator, it's easy to see that Zynga stockholders can thank the Facebook bump for about a 40 percent increase in their portfolio value. Next time you see Mark Zuckerberg on the Street, Zynga stockholders, be sure to give him a fist bump.