Tumblr said today that users can opt out of advertisements (on the desktop and in its mobile apps) for $4.99 per month or $39.99 for a year of ad-free browsing. Long-time posters will be able to return to the way things were before Yahoo purchased Tumblr for $1.1 billion in 2013, before Tumblr prohibited pornography and lost a large portion of its following, and before Verizon sold Tumblr to WordPress owner Automattic Inc. for a fraction of its initial price. Founder David Karp was adamant about not allowing commercials, and once the firm adopted that stance, it was inundated with garish, cheap-looking ads that seemed to swamp the stream and often made little to no sense. Anyone who still uses Tumblr may now get the ad-free version of the site if they pay a fee. That pitch isn't as compelling as it was when Tumblr was at its most popular, but it does indicate new indications of life for the site, which may be appreciated by anyone who has stuck with it through the changes. Of course, another approach to reassure long-time users that Tumblr has a future is to add more free features, and its new blog viewer on the dashboard is a good place to start. Here's a free suggestion for your next move: Tumblr NSFW is $14.99 ad-free and unblurred, which is less than HD Netflix.