Or, to be a little more "comprehensive" (and slightly less conventional, though still not seriously hard to "decrypt"), you could try "rot-23" -- here it is expressed with hex character codes (because hex is just easier for me, somehow): 
perl -pe 'tr{\x20-\x7d}{\x4f-\x7d\x20-\x4e}' clear.txt > cipher.txt

[download]
And of course, doing the same thing on "cipher.txt" will turn it back into the original "clear.txt". This affects not just the alphabet letters, but all "printable" ascii characters from space through close-curly-brace (it leaves tildes alone, because you need to involve an even number of characters, and mutating spaces does a lot to help obscure the cleartext -- though it won't take someone long to figure out which "coded" character represents a space).

In reply to Re^3: encrypt and decrypt text by graff
in thread encrypt and decrypt text by pearlie

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