By Minal BopaiahSo it’s that time of year, when the staff at Subscription Site Central disappears into the analog world to do analog things. (There’s no proof, but some of us have been known to moonlight as Santa’s elves or masquerade as those people who actually buy printed books.)We’ll be returning on January 2, 2014, but  in the meantime, we want to leave you with the top 10 most-clicked-on posts of 2013:#10. TheStreet Makes $10.4 Million from Online Subscriptions#9. Google Kills Keyword Data and PageRank, Makes SEO More Obtuse#8. Case Study Lessons: When Launching New Subscription Products, Create Single Sign-On for Existing Subscribers#7. The Genius of On-Site Reminders for Getting Updated Credit Card Numbers#6. Advanced Tips to Optimize Online Forms for Subscription Sales#5. Email Marketing for Subscription Content: Getting Past the Basics#4. Should Subscription Sites Let Subscribers Opt-Out of Auto-Renew?#3. When Bad Site Design Garners $1.5 Million in Subscription Revenues#2. Top 5 Mistakes in Paywall Design for Conversion Optimization for Subscription Sites#1. Get Your Subscriber Emails Into Gmail’s ‘Primary’ InboxHowever, I should mention that we recently discovered that getting subscribers to alter their Gmail settings, as we recommend in our #1 most-clicked-on article, is actually not that effective. Nevertheless, Gmail’s Promotion tabs seems to be helping marketers, as we discuss in our recent post: Email Marketing May Get Easier Because of Gmail Tabs.Of course, a Top 10 list can’t begin to represent all the topics and information we’ve covered this past year. So, dear reader, what was the most helpful article you read about subscription digital content this year? Paste it below in the comments section to share with everyone!