Earlier, I had been watching "porn for pyros" spam itself over a fifteen minute period over many variations. Because it had been spammed rapidly in sequence, it got entered into many banned lists and thus anyone searching for it would end up with nought.

Something like this could be stopped by having two sets of banned items. One list is manually entered and it either never expires or expires after a period of time. Another list contains the automatically picked up list of banned words and those terms expire after a randomly determined time between 4 to 7 minutes. Why the random variation? Well, that is to prevent lockstep engaging/disengaging of banned terms across the entire gnutella network. One day, we will all have +500mhz CPU with cable/dsl connects; in that scenario, we could have a lockstep propagation...