Happened to my parents and me, back in the mid-90s. Luckily, nobody was in the kitchen the moment it happened. All I remember is that it left a decent dent in the vent hood above the stove, and Gulasz... Gulasz everywhere.
Then again, I was also right next to an exploding Mokka / Espresso stovetop cooker, so maybe I am simply unlucky :)
I still own a pressure cooker and use it regularly - a cheap one from IKEA at that.