Unwritten Alternate Universes

[browngirl]

vassilissa's post about MCR in Bujold's world of Chalion made me curious about unwritten AUs. What are your ideas for alternate universes for fandoms, characters, and settings that you love?

As for me, completely unsurprisingly I have Minoan ideas for NUMB3RS and Doctor Who, but I've talked about those both before. One AU I'm probably never going to write, because it would be so very thoroughgoingly dark, would be what would have happened in LOTR if the Tookland had fallen to the siege the Men set on it. I even have an idea for how the Battle of Bywater could still have been won, but with that gaping hole in the Shire the entire tenor of all that came after would have been changed.

Surprisingly, I haven't come up with any AU ideas of the fashion of vassilissa's above, where one moves a set of characters into a fictional world; this has often had good results with RPS (I remember a couple of lovely stories where the LOTRPS cast were placed into other fantasy universes) but now I find myself envisioning Young Justice in Oz, and I'd better stop giggling before my boss catches me.

*giggle*