And pretty is subjective, i find the Win9x, Win2K, OS/2 (...to some extent), BeOS, and KDE1 icons better looking than the more recent ones which are usually mon

And pretty is subjective, i find the Win9x, Win2K, OS/2 (...to some extent), BeOS, and KDE1 icons better looking than the more recent ones which are usually monochromatic. The Win9x icons tried to be colorful but also were limited by a 4bit palette, which meant that they were both high contrast and had bright colors. Win2K icons are a softer version of those and KDE1 icons are what you'd probably get if you tried to make icons in the style of Win9x/OS/2 but without the technical limitations. I was never a fan of WinXP and Vista/7 icons, too plasticky, often faded out and shiny. I did like macOS icons before they decided to get rid of skeuomorphism and made everything like it was designed by a 5 year old with a vector application. They were high quality but also had high readability. As a developer i hated them though because they were very hard to make something decent. I also like the GNOME 2/Tango style and the elementaryOS style which seems to me to be based on Tango. Tango is a bit WinXP-ish but i think they did a better job with making the icons less plasticky and more readable. But my favorite is the Win9x and KDE1 styles because of both how they look and how easy (relatively speaking) is to make them (which is important, otherwise it is hard to get a consistent look).