Windows Vista 32bit & Ubuntu 64bit on my Desktop. I also use Windows 7 on my laptop.
Gotta agree here, Workbench 3.1 with Imagine 3d…Hell yeah!
Yeah it looks like its a great OS though I got to admit I never given it a serious try. I consider however Amiga 500 by far the best computer ever built and I just loved anything that came out of that machine.
Since someone else mentioned Basic I will have to note here Squeak . Squeak is a modern implementation of smalltalk that dates back 1969. The very first programming language to implement a GUI and Object Orientated programming and also one of the first to use a mouse. Its not just a programming language , not just a platform for making application , but an environment filled with developer and user tools some of them related to graphics and other to music and sound. Also it is the first to implement a VM (same VM has been used as the basic for the Java VM). If some of you code in python you already using smalltalk’s prime features.
It can even be used as a standalone OS , though its tricky to make it work because of the very limited driver support. But by itself is basically a OS run inside another OS , and of course works for windows, macos and linux. I am creating a visual coding project that will be used to control both blender and gimp and it is based on Squeak (and Pharo) so I may be developing my own sort of OS afterall 
Have to agree. I could duplicate a stiffy, listen to music and play a video with no impact on the cpu. Can you imagine an Amiga, if all the chips copper, agnes, blitter etc where all running at current speeds and fabs sizes, would compare to todays monolith pieces of shite?