Karma, no matter what you do it will come back to bite you where it hurts the most. Up to 20,000 pirates who thought they would get away without paying for iWork '09 have learned that the hard way.
A recent copy of iWork '09 was leaked to the web but contained a free bonus add on, a virus called OSX.Trojan.iServices.A. This virus does the nasty work of installing itself in the startup as root. It then goes on and broadcasts its location and allows for malicious users to take over your Mac and install anything they want and modify files already on your computer.
It goes without saying that people who stole this software will probably have a hard time removing the malicious program because of that nature it was installed. Karma has certainly come full circle to those trying to pirate software.