Dark Matter

 Dark Matter is a material found in the popit menu on LittleBigPlanet and LittleBigPlanet 2.

In LittleBigPlanet 2, there is another material exactly like Dark Matter except it's called White Matter and it's white and more slick.

Glitches
Dark matter has a number of glitches including the invisible floor glitch which is made by making dark matter as small as possible.