shmem is right about perl2exe. PerlApp is more difficult. You won't find any text strings to display. In older versions, they just XOR'd the script with a fixed string. What they do now is more sophisticated and harder to figure out. But at some level of effort, it is possible to figure out. This is not NSA encryption!

I figure a main question is would be what the OP is trying to protect against? Insertion of malicious code? "Stealing" his software?