• Code whose function is not immediately apparent to anyone
• Make your code as compact as possible, get rid of that needless whitespace, make things as confusing as possible.
• Don't be too cocky with your post. You'll (almost) always get a reply that does the exact same thing in even less characters

While the Obfuscation section is not restricted to JAPHs, they are by far the most common. JAPHs in particular are usually expected to be no more than 4 lines of 80 columns each. To be 100% consistent with the original JAPH by merlyn, it also needs to produce the following exactly:
Just another Perl hacker,

Look at Separated JAPH/Obfuscation sections.

But more can be found at these nodes:

• list of great obfus
• Writing highly obfuscated code in Perl
• Deobfuscation for fun and profit
• Principles of obfuscation?

HTH

While this is not exactly the canonical rules for JAPH, you might want to read this nice meditation for background information: The Lighter Side of Perl Culture (Part II): JAPH.

Just encrypted sounds good to me, so long as the decryption is part of the post. In Red Perl part I, I basically just decrypt and print a string, with only a little attempt to obfuscate the decryption routine.