Struggling to find good stuff and the 'popular on Facebook' selection is always pap. Thought it would be good to invite random recommendations as I'm sure there's some hidden gems in that vast library.
Here are some of mine:
King of Kong - superb documentary on arcade gamers racing to reach a top score. So so good.
Weeds - darkly funny US series - drops in quality after first couple of seasons but well worth a watch.
Scratch - geeky documentary on the birth and evolution of scratching / hip hop.
Whip It - full of cliches but funny and well done.
Youth in Revolt - slightly random comedy but very funny in parts.
Glengarry Glen Ross - finest swearing ever committed to film. Stellar cast.