Icarus players read no further....
As Dan, the flighty narrator, struggles to avoid the lure of the Star Wars universe (must make it to ST:TMP DVD... :)) I've been tinkering with a background for the Constitution-class Icarus during the 23rd century.
Inspired by the Middle East during the Cold War, I have the beginnings of an idea. Basically, we have a civilization, a deeply religious people who a few hundred years ago had achieved major scientific advancements on their homeworld, just short of FTL travel (which they had "proven" as impossible). They sent out colony ships, colonizing a dozen worlds in nearby systems. However, their civilization, limited by sublight travel, stagnated and was damaged by civil wars on the homeworld.
Move forward to the 23rd century. These peoples (not a united government but rather a dozen or so pricipalities) have purchased warp drive from the Orions and find themselves as minor powers, though wealthy ones, due to the high concentration of dilithium (i.e. oil) on most of their worlds.
In the Cold War between the Klingon Empire and Federation, the various principalities have ever-shifting alliances between the various major goverments, with the Orions always seeming to make the most money. However, things will soon be coming to a head with a major religious revolution (orchestrated by the Klingons) on a fairly secular world currently allied with the Federation - I have visions of students storming the Federation embassy.
Obviously this is just the beginings of an idea, but comments as always are appreciated. What I'm especially interested in is some religion which unites the various worlds. Despite the obvious cultural parallels with the Middle East, I'd prefer to avoid basing their religion off of Islam or Judaism. I'm looking to create a religion with tons of possible variants. I also have a tendency to whip out the Iconians every fourth adventure so to avoid being a cliche I'm trying to avoid making the religion based on any "godlike alien of the week".
These worlds will not be the be-all, end-all of the campaign - there will be many unexplored worlds in the region as well, along with the occasional Klingon or Federation colony.