XRay is a much-expanded version of the Finder's "Get Info" window. It's US$10 shareware.

[XRay 1.1 has some issues with Leopard, unfortunately. Expect a beta of XRay II in late 2008.]

Select any item in the Finder and press Command-Shift-X, or simply drag any file, folder, application, or volume onto XRay's icon, and you'll get a information window:

All enabled flags and fields can be edited; if necessary, XRay will ask for an Administrator password to change files you normally wouldn't be able to modify.

You can also XRay a file from the Finder, using the included Contextual Menu, or from any XRay window by opening the built-in browser drawer:

Beyond the basic item information panel, XRay also has a panel for viewing and editing file permissions:

and yet another panel which shows/edits type, creator and extension and explains how they affect file-application binding:

All these facilities can be configured by a comprehensive preferences system:

XRay's capabilities can be infinitely extended by third-party plug-ins, several of which are in development.

XRay can also move files to the Trash, empty the Trash even if it contains locked or protected files, create 5 types of aliases and symbolic links, and do many other useful things.

Try it out! It will work full-featured for 15 days; after that, you'll be able to use Administrator authorization only once per run.