I will talk about various mechanisms by which an RNA polymerase can interfere with the transcription of genes other than the one it is transcribing. These mechanisms are less talked about than activation or repression by transcription factors, but it's not surprising that intricate polymerase-dependent transcriptional control exists -- RNA polymerases are after all DNA-binding proteins themselves. I will give a brief overview of experimental and theoretical work on this, some of which I've been involved in.