Anyone here read Hieda no Akyuu's Ambience series of fics?
He's got two of them up,
Ambience: Platoon (Moebius Four) and
Ambience: A Fleet Symphony
In both stories, in the wake of 9/11, the US Navy, in collaboration with their Japanese allies, begin developing naval weapon platforms that were compact, like the size of a human. Essentially ship-girls. However, both of these fics are alternate universes of each other.
Platoon Moebius 4 is a diary of a USN Commander sent to Okinawa and tasked with commanding the fleet of ship-girls, which in this fic were made for the JMSDF, and essentially takes place in our 2014.
Fleet Symphony, however, is an alternate universe, where the project was rudely interrupted when the US and Iran started chucking nukes at each other in this universe's year 2010. In addition the project was developed by the USN, FOR the USN, and a handful of the girls never made it to their final destination when the bombs fell. The story opens, in 2029, with a post-war-born waste-lander having found a lead to where one of the girls were kept, leading him to a basement in the ruined suburbs of Houston, Texas, and comes face to face with
Murakumo
I actually found Fleet Symphony to a very gritty spin on the franchise, despite verging into uncharted territory. Seeing the ship-girls fight as both conventional infantry, and then quickly switching to their naval roles was quite interesting too.