Getting vBulletin from Kazaa would probably not give you too much trouble, unless someone finds out, since there would be legal consequences. However, getting hacks for the board without a license is another story. People usually don't put them up for download since there is a perfect source for them, and downloading them without a license would almost prove to be impossible.

"Stephen Wolfram is the creator of Mathematica and is widely regarded as the most important innovator in scientific and technical computing today." - Stephen Wolfram