Warp coils and photon torpedoes aside, have you ever thought of the weird fact that there's no money in Star Trek? Or how people get stuff done in real life when they can just ... erhm, enjoy what the holodeck can offer?
Our very own John who blog at The Zeray Gazette has, and he's given it some serious thoughts:
... my usual interpretation of the economics of Star Trek: they were unrealistic, as they eliminated the first law of economics -- scarcity. Thanks to the replicator, there is virtually no need to manufacture anything. Although there were a few objects, such as latinum or yamok sauce, that could not be replicated, there was essentially nothing that your replicator could not provide for you -- including more replicators.
Come to think of it - how would a money-less economics of the future a la Star Trek work? Who'll do the scut work?