Here's where it gets interesting: What sites and services do these accounts connect to? They're not saying. Maybe PayPal, Amazon, Facebook... your local bank. Who knows? A representative from the security firm F-Secure thinks they might actually be from the somewhat obscure Web site called Writerspace.
Since it's not entirely clear where these usernames and passwords came from, you might want to make sure you haven't been compromised. Rather than downloading the LulzSec file yourself, Gizmodo has set up an easy testing center. Just enter your e-mail address and, after a few moments, you'll know if you were compromised somewhere.
You still won't know where, but perhaps you could take that as a sign that you should start changing your passwords. Be sure to use a strong password when you do.
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