Need to know more details about a file inside the Open or Save dialog boxes? Select the file(s) and press Command-I (the Get Info shortcut from Finder). This will bring up the Get Info panel for the items you've selected. Note that Command-Option-I doesn't work.
If you want to open the file's enclosing folder from the Get Info panel, hold the Command command key and click on the filename in the window title.
Mac OS X Hints
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