The one's that I know are, in order -

1. Hacker News - https://news.ycombinator.com
2. Reddit - https://reddit.com
3. Product Hunt - https://producthunt.com

There are many other resources like https://startupmate.flammate.com & various others but they give a lengthy list of resources. So opening a new account on all those 1000+ sites seems too much for one guy. So other than the above 3 which websites do you think drive the crazy amount of traffic ?