Last week I finished the novel I have been working on here and there since March 2008, taking several months off at a time to take fiction courses and do other things. This is a first draft, and finally weighed in at 164K words, so clearly a lot more than it's likely to be if it's ever tidied up and re-drafted. (It is only a third of the length of War and Peace, but then War and Peace is better written.)
It was a bit of a surprise - I wrote the ending of the main plot, knowing I had a couple of sub-plots to tie up, but then went back and finished those on the same day as I suddenly knew what I wanted to do. I've mostly celebrated by telling people IRL.
A bit of an anticlimax followed - I took a few days off writing, partly because a massive art project was coming to completion too, then carried on with my research for NaNo. I am now ready for the NaNo writing to start, but in a way apprehensive - it feels like so much more is at stake now that I have finished two novels and been taught The Official Proper Way to Write, and what if I fall on my face? Reminding myself it's supposed to be fun sometimes works for this one.