Comment by cosmic_cheese

On the Mac side of the fence, Kaleidoscope schemes were even more capable in terms of deep desktop theming, giving the artist full control of just about everything (window chrome, controls, icons, fonts, desktop pattern/picture). Even better, they didn’t require any installation step: double-clicking a scheme file was all that was needed to radically transform your desktop. Nothing matches its capability and ease of use even today.

Artists did some wild stuff with it. A few fun examples:

https://macthemes.garden/themes/c7005c70d044-Wrecked-Angles/

https://macthemes.garden/themes/2852d54a73a3-Windows-98/

https://macthemes.garden/themes/0219829f8a23-HolySmoke/

https://macthemes.garden/themes/8405ec7f05e4-MacPlaza/

https://macthemes.garden/themes/92b39d18db52-MammaMia/

https://macthemes.garden/themes/9a95c2efce50-Scanline/

https://macthemes.garden/themes/64bd1a86e9e6-Onyx/