Cool puzzle

Here's a series of cool puzzles, if you're a developer (or otherwise a [computer]geek): Toughest Developer Puzzle Ever. Despite its name, I personally didn't think it all that tough as only puzzles 25, 27 and the very last one gave me any trouble. The one is where it tells you that you've won... as you haven't quite. There's one puzzle left there, and it's a toughie.