FileXaminer is like the Finder's built-in Get Info (??? - i) on steroids. The features are manifold, allowing you to edit permissions and ownership, dates, type and creator codes and much more. It's particularly handy for editing file attributes that the Finder simply won't let you touch. There are some very basic icon and image edition functions as well, but it is mostly a GUI for editing UNIX level file attributes.
In addition, FileXaminer also adds contextual menu items with handy functions like copying a file path (for use in the terminal, for example) and Super Delete.
FileXaminer is $10 and a demo is available.