This question already has an answer here:
Prompted by Good documentary videos related to the sustainable living? , I've commented:
as it's phrased at the moment, there isn't a single definitive answer: it could only be answered by a big list. On the other hand, in their early days, many sites do seem to allow these big-list questions, with the content then getting fed into tag wikis.
Once the site is mature, I'm taking it for granted that our policy will be to close & delete such questions.
However, on other sites, these seem to have been a good way in the early days to gather great content and attract new users.
So, what shall we do now, while the site is young?