In the 90s there was a file manager solution for Amiga computers called Directory Opus. It was a two pane file manager with shortcut tabs to paths and devices, and it could do anything under the sun from mass renames to site to site ftp transfers. It was the GOD of file management.
Later, it turned into a full GUI replacement for the Amiga platform. It was then called Opus Magellan, and could do even more from automatic conversions of document formats, ZIP/LHa folders (where archives were treated as folders, and you could FTP in/out of them). Also, when you were connect via FTP to a remote site, if you clicked twice on a file, it would open in whatever default app was set on the local machine. If you just quit that app, the temp file was automatically deleted. But if you did a 'save as' or used a hot key when clicking twice, it was downloaded as is, and opened.
The file manager interface was icon or text listing based, and you could customize the toolbar to your heart's content, including creating custom droplets like "lha -a {x}" or whatever. It was like integrating a full shell command interface into buttons in the file manager's toolbar. It make things like image conversion lightning fast as command line utilities alwasy trigger faster and perform faster when you leave them behind the scenes without a GUI.
The interface was fully skinnable and many commercial skins were available. Some were even full window/gadget/widget API replacement packages. If I recall, one was called MUI, although Opus was pretty much that in itself anyway. Patterns, and desktop pictures were all applicable to window borders, icon alpha channels, you name it. You could map a pattern to the transparent parts of of icons and do some really fun stuff without having to ever open a graphics app.
Anyway, forgive the nostalgia but I'm still impressed. This software is now on version 8, for Windows:
http://www.gpsoft.com.au/Index.html
Although it's not a GUI replacement anymore, it's still the most powerful file manager I have ever seen. It has so much power, it's like having one application to replace the Finder, Transmit, iPhoto and more.
I would love to have that product available for the Mac! It would be awesome to be able to create an archive (gzip let's say) of something, upload it to an FTP server, and then when the need came, upload into that very same gzip. Software authors could update their Readme files, or user manuals on their distribution network without having to manually replace the old file, rearchive, upload, replace etc. Granted, these steps need to occur anyway, but it would be automated right from the file manager.
The older version of the application (version 4) is open source now and can be obtained through here:
http://dopus.free.fr/ .
Nostalgia pic:
Directory Opus 4 on an Amiga
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