Tool/Nightmare Fuel

"Rosetta Stoned." Has The Narrator been abducted by aliens, or is he just doing the Mushroom Samba? Either way, it's really fucking scary. Listen to it stoned.
Here's something "fun" to do: stay up until 3 am, then turn off all the lights and listen to Lateralus all the way through. By the time you get to "Faaip de Oiad", you will be paranoid beyond belief.
- "Faaip De Oiad"'s sample comes from a phone call into the Art Bell radio show. Another band called The Faceless uses the exact same phone call in a song called "Planetary Duality".
Tool songs fall under two categories, Mind Screw, or Nightmare Fuel. The best ones do both, with often incredibly disturbing results. Take for example, "Disgustipated" from Undertow.
- The opening track on Undertow is just as bad. It's supposed to sound like someone running out of oxygen underwater.
"Viginti Tres" from 10,000 Days is another good addition to the list of creepy last tracks.
"Prison Sex." While the original song is certainly more than enough to qualify for Nightmare Fuel, it's the music video that is truly disturbing. Try watching it without feeling disturbed.
Listening to "Die Eier Von Satan" for the first time can be intimidating: The incredibly dissonant guitar noises, backward drums, and vocals in a Hitler-esque German voice. Until you find out what he is saying in English: it's just a German recipe for hash cookies. On top of that, the title in German may also mean "Satan's Balls".
- What about the interlude "Cesaro Summability"? God. It opens with a bunch of Ear Rape baby screams, then the whole rest of the "song" is made up of dissonant guitar noises and talking.
The music video for "Schism". Words alone fail to do it justice.