Anything good on your geek shelf?

I’ve been enjoying QNX’s new Pocket Geek game and have come to a few conclusions about the diminutive coder:

• He’s a die-hard command-line user (never touches the mouse)
  
  
• He works in an extreme-programming environment (never codes more than 40 hours a week)
  
  
• He’s concerned about IP contamination of his code (if that isn’t why he kisses his black duck, I don’t want to know about it)
  
  
• He owns a penknife (how else do you sharpen a pencil as thick as your forearm?)
  
  
• He never consults his reference library

Now that brings up an interesting point. At no time in the game does the Pocket Geek ever consult the massive tomes looming over his head. So why does he keep them?

If you’re a techie, you probably have a few reference books on your shelf. Are they all gathering dust, like the ones in the Pocket Geek game? Or has one made a real difference to your skills and productivity as a software developer?

Think of it this way: If the Pocket Geek were to read one book that would raise his productivity to new heights, what would it be? The 7 Habits of Highly Effective People? Extreme Programming Pocket Guide? The Joy of C?