Amazon currently has 145 videos that you can own (not just rent) for $.99 each. I ended up taking 8 of them, using up about 1/2 the no-rush credits I picked up around Prime Day. Some of these are free to watch on Prime (they're marked with a Prime banner in the upper left corner). 6 of the 8 I took were documentaries (all from the 2nd half of the listings) as well as Drug Wars and the 2017 Oscar Nominated Animated Shorts; and there were other items that I was tempted with as well. They've started having some of these show up but haven't seen so many before.
https://www.amazon.com/s/ref=sr_pg_1...qid=1533087517
If you save the link there tend to be a lot of changes week to week.