The only real suggestion I have for you is take the code you want to protect, and throw it in a file as a data segment, and make a self-decripting perl file that takes one command line argument, the key. The entire point of this wrapper perl file would be to read the data in, decrypt, unpack it, and then eval it. To obscure a script language is difficult, no matter what you do, especially if it's heavily bound to the interpreter. If you need to hide stuff away, consider either pack
ing away the string that contains the code (or using Storable
to freeze it)and then encrypting with one of the major perl Crypt::* modules.
Other than that, enjoy the time off. Keep the decryption key.