Land of the Lost, eh? Someday I'm gonna have to buy the original series on DVD. That show was freaky weird.
http://en.wikipedia.org/wiki/Land_of...ies#Altrusians
I'd recommend doing a mod nation combining cavemen with elements from Land of the Lost, except that I'm already working (not very hard) on a nation that summons creatures from the past and the future. It's Lovecraftian, though, based on the Fungi from Yuggoth.
Still, a Land of the Lost nation could be really interesting-with Sleestaks, Altrusians, those crystal matrixes they used sometimes, pylons, skylons, the Library of Skulls, dinosaur summons, invisible aliens, and other weirdness.