TextWrangler prompts for authentication when saving to a write protected file that it's opened, but won't allow saving to one with a different filename (e.g. using "Save As") if the directory is write protected. And it only allows overwriting writable files in directories not owned by the user if it's opened them.

Someone more familiar with TextWrangler may know better. I won a copy the other day so your post was a reason to test it and reply.

How I wish SubEtheEdit could do that out-of-the-box without any tricks (sudo SEE). It is a very nice, cocoa based, free, colloborative text editor written for OS X, not a port of an aging app (re: BBEdit) that costs more than the OS it runs on...