I got carried off by the spirit of inspiration yesterday and wrote five pages of the epilogue to Book 12. Set way, way, way, way, way, way, way, way, way, way, in the future from the events in Book 08 (which I am ostensibly working on).
I had been playing around with two different ways for the series to end, either of which precluded the other from happening. Then, while jogging, I figured out how I could do both. Granted, there is a little deus ex machina involved, but not too much... I hope.
Obviously, I don't want to give too much away, but the epilogue is about Commander Keeler, and it is built around a scene reminiscent of the ending of The Restaurant at the End of the Universe. That's all I'm saying.