Someone has probably already done this, but it occurred to me recently.
Several months ago I splurged for $3.99 and downloaded a Scrabble game for my phone. Since it's not a smart phone, it's not a "play against your friends" kind of game. It does have a pass & play option so you can pass it to another person and play a two-player game in real life. Or you can play solitaire or against the computer. Someday I might have to post a rant about how this game must have been programmed by a semi-literate, politically correct feminist, but now is not the time for that.
My idea would have to be played on an old-fashioned board with real tiles and so forth because the electronic versions are all hard-wired to prevent anyone breaking the rules. So here it is.
Play as normal, except: words/names (yes, proper nouns!) are allowed, but only if they appear in The Hobbit/Lord of the Rings. If you play a word/name that appears only in Hobbit/LotR (or at least originated there), you get bonus points. Which means it could be a multiplier or just a straight specific amount of bonus points, I'd go either way. Alternatively, words/names that are specific to any sci-fi/fantasy book could be allowed if the players all agreed. Except if anyone spells a word or name from any of the Shannara books you lose points.
I must admit that I sometimes pass up a higher scoring word just so I can spell a word that I think is cool--exeunt, for example. Although if you can put that on a word multiplier it adds up pretty well since X is an 8-point letter. And recently I got away with using "taxon," which I wasn't evens sure was a word on its own. Anyway I think it would be really cool to be able use "Bilbo" or "M*rg*th." I suppose there would be arguments as to whether such words as "shire" would get you bonus points or not (I would say no).
By the way, so far my best single word was "squinted," for which I got 122 points. Not that I actually can remember that kind of detail, but the game keeps track of that. I've been able to use all 7 letters three times.
I still haven't been able to use "zymotic" or "squamous," although I did manage to play "gibbous" once.