There had been a couple of problems with my recent article on Blender Particles (http://www.packtpub.com/article/advanced-effects-using-blender-particle-system-sequel) lately, being the .blend file on one of the boids examples corrupted/incomplete on Packt's link. My apologies to those who have tried and failed in opening the file.
Anyhow, I'm now reuploading the file myself. If there's any problems, please feel free to contact me at reynantem[at]gmail[dot]com.
Here's a download link to the file > http://depositfiles.com/files/xktye6a4k