Its a thread about what does your DM do that you don't think many other DMs usually do.
For example my current DM has an annoying habit of knocking everyone in the party out. He's pretty new to DMing so we let it slide but I think for the 20 hours hes been in charge we've been gassed, hit over the head or mind controlled around a dozen times. But we're slowly getting him to change that and the story he has us running through is pretty fun for a first timer.
I also had another DM who had a habit of ambushing us all the time. Whenever we left a town or explored a non-threatening cave we knew that goblins, bandits or whatever was going to ambush us. But he gave us a lot of good loot from the ambushes so I'm not complaining.
So what are some of the quirkier things that your DM(s) do?