I started with Mac OS 7.5, and suddenly I got nostalgic for those old destop patterns, from before the system itself supported large wallpaper images (though you could use a plugin called Decor. Decor was more intelligent than OS X is still, it had more options, including hiding none of the image under the menu bar, which OS X still can't do!)
I had to look around a bit, but a genius named Mike R extracted them and posted them (small zip file). (Backup link.)
Funny enough, admittedly, on a modern high-res screen with its powerful color rendition, many of these patterns, even the more subtle ones, are sort of loud and dizzying.
One reason they lack subtlety is that they were designed to work on screens which could only show 256 colors.