It's not perfect, but it's simple... you might try CipherSaber. Once you get past the political posturing, the basic idea is:
we should emulate the Jedi masters by learning how to build strong cryptography programs all by ourselves.
And then it goes on to describe a simple algorithm (basically RC4) and give some helpful test vectors. There's also a perl implementation you can refer to.

In reply to Re: Anyone has simple encryption mechanism? by Anonymous Monk
in thread Anyone has simple encryption mechanism? by soon_j

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