I was going through my old folders on my computer and found a project I did several years ago, and it got me wondering. Admittedly, the thought was probably at the back of my mind anyway based on a few posts yesterday in another thread about how AD&D was wonky and crossed genres.
So I ask of you, if you could take D&D's default middle age fantasy ...
so, red sports cars? ;P
D&D has always been wonky, a genre hybrid among high-fantasy/S&S, Lovecraft (and a bit of Poe), and science fiction from EE Doc Smith through Vance. It's pretty nuts, but, really, that's what the 70s were like, very iconoclastic, irreverent, derivative, and, well, there's an in-joke over here: "The Decade Taste Forgot." ;P
and push it into another genre, what would it be, and which edition's rules would you use? And tell me why it would be awesome.

I love hearing how people mold stuff to their own ideas.
I took a stab it throwing AD&D in 3 alternate directions at various times, with little success: Star Wars (because no one had the license yet, and kids are impatient); Overt Science-Fantasy based on Moorcock's Rune Staff series (crossed with a bit of Forbidden Planet); and, well, I guess what you'd now call Urban Fantasy - I imagined a 20th century that had a magical D&D version of the middle ages as it's history. So, like, you go to a veteran's day parade and there'll be an elf or two marching in their old Minute Men gear, there are magical Colt Peacemakers floating around that can punch through tank armor, a wizard somewhere along the lines added a radiation component to his version of the fireball spell...
...none of those attempts worked out well, the first was just laughable, the last one never really got off the ground. The science-fantasy one, though, I revisited using Hero later and it was a pretty successful campaign for a year or few.
Edit: oh, one more, almost forgot - after getting 0 interest in RuneQuest I did adapt D&D in a bronze-age setting, just reworked armor & weapons and restricted spell lists because magic was also 'less advanced.'
...oh, also within the context of my long-running AD&D campaign, I did introduce a city-state that used quixotic magic to create all sorts of clockwork items, from repeating crossbows to power armor to ornithopters - all inspired by the Aparatus of Kwalish. And another, 'lost city' with magic that /looked/ more like super-science (and probably was, but the source of that magic was destroyed or altered at the end of the campaign...)..
Anyway, I tinkered with AD&D a lot, obviously. Ultimately, D&D's core mechanics just didn't work well with much beyond sword-swinging, monster-fighting, and over the top (but viciously limited) magic. The system generally failed to capture anything with a modern or action bent to it.
3e, even though d20 was used for all sorts of things, I never tried to take it beyond the basic D&D-Fantasy self-referent sub-genre. I guess in that period I'd use Storyteller or Hero if I wanted anything not-D&D.
4e changed that, a little. With Healing Surges freeing it from the Cleric conundrum, Skill Challenges, re-skinning powers & monsters, and something of an action-movie vibe, it lent itself to all sorts of things. All-Martial-PC games came off feeling like S&S, for instance, without even trying. (For another thing, it did Gamma World a lot better than d20 modern, Alternity, or FASE-RIP did, that's a plus in my book as a long-time GW fan.)
My Feywild-centered campaign visited other worlds that were modern (some downright anti-magical, one /painfully/ realistic), or science-fictiony (no, it's not a Warforged Warlock with a rod implement, it's a Terminator with a plasma rifle), or steam-punk (a couple times actually, it can be a fun little genre in it's own right - and I'd helped anther DM repurpose 4e to run Girl Genius). In a campaign I played in that's gone to epic, we visited the dream-memories of a vanished civilization that turned out to be interstellar, fought nightmare aliens... now that I think of it, that same campaign, had featured a sojurn to a 21st-century world where magic had always work, much like I'd tried to do back in the day, but just, casually, like we spent a few sessions there, retrieved the artifact we were after, and moved on... huh.