Previous discussion: https://hackernews.hn/item?id=6498625

http://youasked.it/ Answer random questions from people on Twitter

I use http://skimhn.com to quickly filter submissions by domain/author/keyword.

Previous poll 2 years ago: https://hackernews.hn/item?id=2368964

Check out Show HN filter on hnapp.com: http://hnapp.com/filter/9205b686fc8b9b396a0d40e43663116f

You may want to take a look at "Don't forget Bob" in gmail labs. Once you pick some email recipients, Gmail suggests more people you might want to include based on the groups of people you email most often.