So... Star Trek idea?

I'm obviously not going to be attempting nano because that would be crazy, but should I decide in the next few hours to fail gloriously in a plan-free actual-plot-not-just-breakfast fan fictional sort of way now or ever:

What would have been a super awesome Star Trek episode? I'm not asking you to plot a story for me (unless you want to?), but seriously, what would have been a TV guide synopsis you'd have loved to see? (Any crew any series, whateva's your fave of the moment, though I have never written classic Trek before so that might be scary and also I have no 'ships except Kirk/Enterprise.)

p.s. I just got SAD when I saw the number 1,667 today and realized it would mean nothing to me this yeeeeear.