I think I mentioned two or three times in response to similar posts the possibility of not giving the client the entire program, and running an ASP style service which would give them a key or the rest of the program over the net once they have paid.
in reply to Closing Perl Source
This guy may have something which a client is willing to buy but it is based on a really simple algorithm or even someone else's module which he cannot justify the hours on. Anyway it gets asked alot because:
1) it is a difficult problem, regardless of the "why do you want to make it secret" crowd, and also because
2) it must not be answered in an easy to find library on PM since everyone keeps responding to the darned question!
Anyway I wouldn't mind seeing people's experience with perlcc/perl2exe tools to hear about those tools' limitations/abilities. In particular I'd like to see what they would do to a PerlWx type application and if it could be made into a single app without requiring a perl interpreter. Here my interest is not obfuscation, but quick gui-based product development.