You won't only get backlink juice from reddit, you'll also get refferal traffic. Just go to subreddits that are related to your site and post backlinks.
This website is the biggest question and answer portal. Building links there would be easy. But don't be spammy.
Pinterest is a great way to send traffic to your website. It performs very good for websites with a lot of pictures like memes.
With Tumblr you get traffic from your posts and backlinks. It's one of the biggest blog platforms out there.
This site is similar to Pinterest but with less popularity
There you can post your pages and share it. It's pretty easy and can send a lot of traffic.
This huge memes site allows you to post stories and attach a link to your post.