The list of things to do with the internet for 2013 had a lot of interesting stuff, but I have an entirely different post for websites that put up lists of their own top internal posts of the year. I may be adding to this over time, as more of them calculate what they've done in 2013.
Some say the era of the blog is over. Well, maybe not. At least I hope not!
Facebook's Year in Review
Lifehacker's Most Popular Top 10s of 2013.
The Best of Longform.
Here Are the Top 12 Moments on Instagram in 2013.
The top 10 single-serving Tumblrs of 2013.
Top Pinterest Pins of 2013.
2013: The year in Digg.
Carl Zimmer's Top Ten Posts of the Year at The Loom.
Ed Yong's 20 Most Popular Posts at Not Exactly Rocket Science.
Virginia Hughes top five and five most underrated posts at Only Human.
The most influential people on Reddit in 2013.
The Best Of BuzzFeed In 2013, By The Numbers.
The Best Dorkly Articles of 2013.
The Best Gawker Posts of 2013.
Read This, Skip That: The Best of The Daily Beast in 2013.
The 40 Best Cracked Articles and Videos of 2013.
The Best of io9's Science and History Stories in 2013.
The best of The Verge longreads.
A Year in Writing: The Best Mashable Reads of 2013.
Imgur's Top 13 Images of 2013.
Screen Junkies' 2013 Bloopers & Outtakes