Out of all the boxed set campaign settings for AD&D 2e my favorite was absolutely Dark Sun. It was unique and in many ways it was very much a fantasy approach to creating a post-apocalyptic style fantasy world. There are a lot of fans of this setting and even though I didn't get a chance to play in a Dark Sun campaign I did love to read official products and imagine the possibilities that Athas offered.
I started re-reading some of the original 2e material for some ideas for creatures to fit into a Mutant Future setting as some of them would be easily adapted to the setting that I am conceiving. One such character concept from Dark Sun which I liked is the variant on the halfling. I really like the idea of these type of demi-humans being out in the wastelands in my O.M.E.G.A. setting.
My concept for them as enemy NPCs would take them a bit farther in how barbaric they are. In fact, I would call them Feralkin to emphasize just how beastly these little people are. I started working on the stats for my Feralkin earlier today and I expect that I'll post the details later on this weekend.