Everyone knows that a decent rooguelike developer will think of every single possible scenario, no matter how stupid, and program in an equally silly error message should you try to recreate some sort of immensly stupid thing. Heck, I can think of two DoomRL examples off the top of my head:
Pushing a barrel in to lava/acid: "Oh my, how stupid!"
Standing under a teleport square while invincible, then a monster attempts to teleport on to you: "ARGH! It feels like someone is trying to implode you!"
So what's the funniest message a rougelike has ever given you? A good example might be from dwarf fortress: "Astor cancels Engrave Stone: Is on fire." or nethack: "He died by getting petrified trying to help a cockatrice out of a pit"
Screenshot recomended if you think it was hilarious enough.