Social Bookmarking websites can not only drive tons of traffic to your blog, but are also a good place to find topics to blog about. The content on these websites are user submitted and voted on by their community.
Digg – If your post gets submitted to Digg, it can drive quite a few visitors to your blog. If your post makes it to the Digg homepage it will drive thousands of visitors to you blog and could even crash your servers, also known as the “Digg Effect.” Digg tends to be geared towards the tech crowd, so if your site is tech related you have a good chance of getting Dugg.
Reddit – Another community based voting website which can drive tons of traffic to your blog.
StumbleUpon – Users on this site blindly go to different blogs/websites based on their interest. Users can give a thumbs up or down based on if they like the content. If your content makes it on the buzz section of Stumble Upon it can drive thousands of visitors to you blog throughout a few days.
Del.icio.us – The most popular bookmarking website. If your site gets bookmarked enough you may make it to the homepage. Adding links on each of your posts to help your readers bookmark it will definitely increase traffic to your blog. Use the sociable plugin listed above to make adding these links to your posts easy.