The Burnt World of Athas

The official Dark Sun website

Elemental Evil and Dark Sun

Today Wizards of the Coast released the Elemental Evil Player's Companion. This is more or less a set of character races and spells. What Dark Sun fans will be interested in is the races, Aarakocra, Goliath, and Genasi (there's even a sidebar entitled Genasi on Athas) as well as a slew of elemental themed spells.

So if you're playing Dark Sun with D&D 5th edition, this is a must own....and it's free!