I made a trick or trap that can be used in any system. I have used it two times, once in Changeling, once in Esoteric Enterprises, both time to good effect. It’s a more atmospheric or moody piece than an actual murder-trap. I designed it thinking on feeding my ´Changeling players natural paranoia.
Of course, you can modify and twist it as you need, make it more dangerous or whatever feels right for your own game or system.