You can use this key to encrypt files and email so that only I can open them. You'll need to use a cryptographic program such as PGP or GnuPG. PGP is free for non-commercial use, and GnuPG is Free. Depending on what program you use for email, you might be able to plug crypto software into your email system. I'm using Enigmail for Thunderbird, both of which are Free.

-----BEGIN PGP PUBLIC KEY BLOCK-----
Version: GnuPG v1.0.6 (GNU/Linux)
Comment: For info see http://www.gnupg.org

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=9omu
-----END PGP PUBLIC KEY BLOCK-----