OSX:
in the finder, if you select \'get info\' you get a \"properties window\" referring to the currently selected file/folder/volume...
by default this window contains:
There is no official way to do this, and any unofficial way will be rathe difficult since Finder is a Carbon application (no dynamic objects to hijack). Additionally, the Finder has been completely rewritten for Snow Leopard, so any hack you implemented now would stop working.