Please buy this! It's a great game and the devs deserve the money for it!
"Everybody who downloaded our game illegally (for free) has now a chance to redeem himself and get the latest version of the game (Win+Mac+Linux) and it’s fantastic Soundtrack only for $5 (instead of $20)."
"We released the game DRM free which means it doesn’t include any anti-piracy protection, therefore the game doesn’t bother players with any serial codes or online authentication, but it’s also very easy to copy it. Our estimate from the feedback is that only 5-15% of Machinarium players actually paid for the game. If you decide to buy the game, you can be sure you’ll support directly the developers, not any big publisher or distributor."