Whether it's software, games, movies or even books, piracy is rampant. There's no denying that, and there's no one that understands the harmful effects of it better than the content creators themselves. Over the years, we've seen some humorous attempts at trying to sway the pirate towards becoming a paying customer, and there's probably little doubt that some have worked.
In recent memory, Serious Sam 3 introduced a monster only in the pirated version of the game that hunted you down indefinitely and was impossible to kill. There's also Take On Helicopters, which corrupted textures on purpose in the pirated version of the game. Humorously, before these mechanics were understood, some pirates took to the respective developer's official forums to complain about the issues. For a game dev, I'm sure a pirate ousting themselves in public like that has to be oh-so-satisfying.
The two-man team at Greenheart Games understand all-too-well the effects of piracy on smaller developers, so they took a cue from the above examples and made what I feel is the best possible method of portraying the "piracy is harmful" message. Their first game, Game Dev Tycoon, allows you to create a development studio from the ground-up - essentially mimicking what they themselves are trying to find success with. In the pirated version of the game, which the developer itself was first to upload, you'll eventually face the wrath of pirates:
You might think that such a blunt message would clue most gamers into the problem, but not so. On both the developer's own forums, and even Steam's, gamers have been complaining about the issue. One gamer even asked if there was a way to research DRM! It's not bad enough that these gamers pirated the game, but they're complaining about the issue of piracy affecting their progress! The irony is incredible.
To help drive home the fact that piracy is harmful, Greenheart Games revealed their initial sales information, which also includes those who've been playing the cracked version. On day one, the company took in 214 sales (at $8 a piece, that's $1,712 for a year's worth of effort), while 3,104 users were using the pirated version.
6.4% legitimate customers vs. 93.6% illegitimate customers. It's rather striking, especially when the game costs a mere eight bucks. With these results in-hand, the developer has made an appeal to those who pirated the game, asking them to consider purchasing it if they like it (seems fair). There's a lot more meat at the URL below about this whole process, and I highly recommend reading through it.