Personally I feel if you dont want something stolen, dont release it. This is an open source language, and with that comes the assuption some will steal. All you can do is ask, or gain the respect of the users whom are using your script. Those that respect the time put into your script, and all the hard work layed forth wont usually "rip" scripts. They will include a note like "taken from <insert script name here>.
I personally feel the idea of "go ahead and take it". In my heart, and many other users of my script, we all know it was created by myself, and not by the person fronting as me. Secondfly, I built scripts for two reasons. For people to enjoy and have fun with, and to learn from. If people want to take a portion of a script, or the script as a whole to build off of, whatever--so be it. Im more or less a programmer who would follow under the GNU system. Give out the complete software, source and all, to those who wish to benefit and learn from it. Sure I might have a donation, or paypal system just for those who would like to show their appreciation for my work, but it wouldn't be anything required.
Anyways, that my 2 cents. The main point is if you dont want it "ripped", dont give it out.