Plenty of reasons, Bickaxe, some trivial, some not, all contributing the whole state of ennui that I feel. However, two current reasons come to mind: I have writer's block, and the announcement of the TP Prize shortlisting is soon, and I don't think I'm going to be on it.
Quite frankly, if I posted on this thread every time I was depressed, Tony would have to make a new thread far more often. I only posted now partly because of the TP forum nature of the depression, and partly because I had the brainwave of using an image of, and quoting, Marvin. So even when depressed, I do have a perverse sense of humour. Some of the time, anyway.
Have you seen the size of human brains? They're hilarious!
-The Twelfth Doctor