Yeah, sorry, I don’t really know how to title this little trick. Let me see if I can set this up so it’s clear what you’ll be looking at, before you actually look. (Or you can skip me stumbling over myself and just watch it anyway…)
When you’ve got a window open – be it Firefox, TextMate, etc, etc – there’s a title to that window at the top, and if it’s a file, there’s an icon positioned to the left of it. A nice trick in OS X is that you can drag that icon to the Finder to create an alias, or by holding down the OPTION key, you can make a copy of that file someplace as well.
Also, if you hold the COMMAND key (Apple key if you’re new ’round here) when clicking on that icon (or any part of the title in that bar) it’ll show you the path in which that file resides. So for instance, lately I’ve been going through some Ruby tutorials. The folder structures are many and a few levels deep. As I’m a relative n00b to this, the folder structures lose me quickly, so being able to CMD click on the title/icon at the top of the window and quickly see where I’m at is a huge help.
Ok so you’ve basically got it now. Below is a quickie screencast I recorded so you visual folks can get the idea. There’s no sound – it’s not broken, I just didn’t record any.
CMD Windowbar Trick (no sound!) – 5mb