I'm putting together a possible game involving the whole of Africa being shifted out of our reality in 1941. What shows up is a land ruled by steam age humanoid dinosaurs who use apes as slaves/animals. They have trains criss-crossing the land, and mastery of gunpowder and airships. They're probably about 50 years behind Europe, but it won't take them too long to catch up, and they have a lot of resources to draw on.
The party will crash land because of the event, and be stuck in the middle of an alien environment. The rest of the world was uneffected by the event, but obviously this changes things. Rommel was on his way to North Africa when things happened, and he's going to have something to say.
I'm really not sure just how I'll play things out, but I'm thinking that the party will hook up with ape rebels to take on the dino-people.
I just started working on this idea this morning, so it's still a bit rough. :hat