Please stick to the former. I do not wish the technique described here to be used to such ends. I firmly condemn them. It may not seem to make sense at first, if you are not used to this kind of methods. The principle is very simple.
People distribute samples of random data.
We call these samples pads . A pad is a file containing random bits, completely indistinguishable from white noise, and of a fixed length. Each pad should be given a name such as pad9f2a2ec68e3729fa.dat , where the 16 hexadecimal digits following the letters pad are the 8 first bytes of the pad's data. This is so the pads can be recognized. This naming convention, by the birthday effect, lets us issue billions of pads on the Internet before we risk a collision.