Or, if you want anytime, anywhere access to your files but don't want to entrust your stuff to anyone else, you could use a Net-connected storage drive like Western Digital's My Cloud to create your own personal cloud-storage solution.
All the rest
We've taken care of your major online accounts, but what about all those random accounts you have connected to your social networks? Go through the settings of your Facebook, Twitter, and Google+ accounts to see the list of apps and services connected to them. Then simply remove access permissions for the ones you no longer use.
Speaking of apps and services, part of good data hygiene is regularly deleting accounts you've left by the wayside. Go ahead: Close that MySpace profile and kill your Klout score if you're not using them.
The tip of the iceberg
Now that you have at least some of your data under control, you could look at numerous other things, as well.
We briefly touched on restricting who can track your browsing while online. For a real eye-opener, try using Abine's DoNotTrackMe add-on for a week and see how many tracking cookies the add-on blocks. You could also use a stand-alone email program configured using the POP3 protocol to save your email locally and wipe your messages from your provider's servers. (Here's the info you need to do just that with Outlook.com, Gmail, and Mozilla's Thunderbird client.)
For an even more comprehensive look at the topic, check out Macworld's seven-part series on protecting your online privacy—but note that some of the tips apply only to Apple's ecosystem.
Going off-grid online is borderline impossible these days, but taking just a short time to tidy up your online footprint can pay big dividends for your security and your privacy. And remember: It's up to you just how far down the rabbit hole you go. Happy deleting!
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