Does anyone remember the Norton Desktop shell for Windows 3.1? It turned 3.1 into something beating the Mac in terms of a desktop experience. Absolutely amazing levels of customization, a full shell scripting language with GUI components reminiscent of Tk/Wish, I could go on.
That desktop plus the whole set of Windows 3.1 programs were a killer combo.
Shame that so many interesting GUIs like this simply fell away, and meanwhile my Linux GNOME desktop still doesn't feel as obvious and powerful as that machine did back in 1994.
Well, there was also the MC Shell, you can get a copy from here (in case you get an attack of nostalgia and have a VM or a spare old-old machine available):
That desktop plus the whole set of Windows 3.1 programs were a killer combo.