(MoneyWatch) There are a million ways for hackers to gain access to your online accounts. There is much you can do to protect yourself, such as using unique passwords on every website, using strong passwords and staying vigilant to phishing schemes. Even those precautions might not be enough, though -- no matter how careful you are, one or more of your accounts might eventually be compromised. And you certainly don't want to find out the hard way.

Rather than waiting to get locked out of your email or LinkedIn account by a hacker, get proactive. Pwnedlist is a monitoring service that can let you know if your email address ever shows up on a watch list of stolen credentials.

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Pwnedlist is a free service that aggregates data from a variety of sources that track security breaches. When you sign up, you get added to a mailing list that can notify you if your email address shows up in their database of breached accounts. The database is updated daily and currently has about 24 million entries.

You don't even have to sign up to find out if you're safe. You can visit Pwnedlist and manually enter a search for your email address for instant feedback.

So what happens if your results are positive? Well, it doesn't necessarily mean your bank account is getting siphoned -- it means that one of your accounts is exposed, though it doesn't imply that any hackers have acted on that data. Clearly, you'll want to change your passwords right away, and be sure not to reuse site passwords.

Photo courtesy of Flickr user JermJus