If you feel that there is a good reason to share someone elses code we aren't opposed to that. In certain situations it seems inappropriate and unfair to the original author. In others it seems really helpful. At the very least credit the original author, or say why you can't. (I.e. "I think I got this from blah.com, I feel it's helpfull but can't remeber the authors name.") Aside from that we have no specific criteria about what is and is not acceptable. If it happens it'll be discussed. It is a touchy subject, treat it as such and you will be ok.