Fans of Gene Wolfe's magnificent Book of the New Sun far-future novels will recall that the traditional color of the Guild of Torturers was fuligin - a fictional light-absorbing hue blacker than black.
I think that almost makes up for the now shaky scientific basis of Wolfe's technology for transferring memories from person to person.
If you want fuligin cloaks or garments in a D&D game, you will have to visit one of the Underdark's disreputable bazaars, bringing with you at least 1000 gold pieces worth of treasure; or take them from those few underground elves who have learned to weave elemental darkness into spider silk. Covering your body near-completely with fuligin, with black masks or veils over one's face, black gloves, and all equipment painted black, gives a +4 on d20/+20%/+1 on d6 for hiding in shadows. Wearing fuligin in public will attract awe, fear and no small amount of attention.
Researcher in social science and appreciator of hexy wargames, role playing games, interactive fiction, board games, and CCGs. I've learned a lot doing design and rules editing work on the side for the Legend of the Five Rings CCG. But this blog is mostly about other things.