[Traps] Oil into the fire

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Whatever happened to all those wonderful traps of yore? I know that traps in dungeons always seem to be a bit superflous in the modern systems (“Roll if you see something! You find a trap. Roll if you want to disarm it! You disarm it! You gain 40gp and a +1 dagger“), but I remember all those wonderful trap collections from earlier times, beautiful ideas and reading material in themselves. So I wonder where that part of the Renaissance is. Did we do traps already and the hat got old? Are inventive traps passé? Did we all decide they aren’t worth it? Are the standard traps enough for everybody? I always had the experience that players loved traps. Well, not traps themselves, but surviving them. They are often one of the most entertaining parts of the whole adventure
Here’s one I thought about a few days ago, while making hamburgers:

Oil into the fire
The characters come across a trap that seems rather harmless at first: a flight of stairs, going down, becomes harder to use when all of a sudden oil (to the referee’s choice, but should be flammable) is squirted or dropped onto the stairs at top, and is now slowly creeping down, making the stairs nearly impossible to climb. It seems that certain stairs have a trigger that causes this effect. What was an easy way up becomes very difficult with a bit of fall damage. What was an easy way down becomes a slide.
The real danger comes afterwards: there are guards in the room at the end of the stairs, they hear the PCs falling down, and they have torches.
For added effect the characters should have ample warning before: a strange smell, like lamp oil. Slippery, greasy stairs, and hoarse laughter from the next room just downstairs.