Was Acorn's RISC OS an under-appreciated pearl of OS design?
I always thought the beauty of RISC OS was in the UX not the underlying OS. The three most important things were:1. Task bar / dock thing. This was well before Windows 95 and Mac OS X both adopted the feature.2. There was a dedicated menu button on the mouse. This was the only way to get a menu, there no menu bars anywhere, freeing screen real estate. The other two mouse buttons were select, which behaved like a normal mouse button, and adjust, which did the sort of things you need to resort to shift-click on other platforms.3. There was no file open dialog. You just double clicked a file to open it, or dragged it to the app that you wanted to open it with if you wanted to open in not the default. To save you would be presented with an icon which you could change the name of, and then drag to a finder window. No duplication of the folder system structure in a finder and in every app that handles files.