An idea that's intrigued me for a little bit. Doubt I'll find the time to write it, but if anyone else wants to take a crack, I'd be delighted to read it.
The mirror universe Uhura is obsessed with the knowledge that she has a double in our universe. She finds away to cross the barrier between the parallel universes and they have a spectacular catfight in Uhura's quarters. Cue the fight music.... :)
For reference
There's definitely an appetite for Star Trek related fiction. Too bad the original series didn't feature Kirk and Spock, surrounded by an array of female officers and subordinates competing for attention, influence and favor. The stories would almost write themselves.