It's so much work to make a movie, and for me it has to get me off my butt. To get me actually writing you have to strike something inside, you have to hit a power main to get the energy. You have to strike something you care about.
Evolution has programmed our brains to find two things particularly interesting, and therefore memorable: jokes and sex - and especially, it seems, jokes about sex.
But we used to go to flea markets and things, and look for old 78 records that had silly song titles.