An Xfwm4 theme based on the "Platinum" style of Mac OS 8/9. Made from screenshots of my own Mac running OS 9 in Classic mode.
Besides the normal version, there's also a version with slightly bigger buttons in the titlebar.
The theme is designed around having one butotn on the left and two on the right, but it still works even if you use a different arrangement. The Mac OS style is close on left, maximize and shade on right.