I like the idea of getting the first part of a movie for free, although I can imagine movies would eventually be written and produced in such a way to hook you in at the beginning with less attention given to the ending.
Well, you just changed my mind. My idea might be great in isolation, but the secondary consequences would be terrible. Hollywood, please ignore the above. I was briefly overcome with insanity.
(In case the strength of the above is mistaken for sarcasm, I'm being completely serious here.)
Reviews, trailers, etc.
Not perfect of course but it's pretty rare that I rent a movie after having done a modicum of research that causes me to think I've completely wasted a couple of hours. (That's not to say that movies don't ever disappoint but that's a different bar from "it sucks.")
When I'm looking at a movie I think I want to see and it's a $5 rental, my thought is always, what if it sucks? And then I usually decide not to risk it.
What I don't get is why they don't offer the first 30-60 minutes of the movie for free. I'll be able to tell fairly confidently by then if it's any good, and would happily pay to see the rest once I'm hooked. Instead, I have to take a guess from badly edited and misleading trailers, and reviews from people whose tastes may vary enormously from my own.