As one who has been with the Mac for many years, I remember when desktop images weren’t actually images at all, but rather patterns that repeated seamlessly on your screen—they were designed such that the top/bottom and left/right edges would flow together perfectly. By then “tiling” this pattern across your screen, you could fill it with interesting patterns. In fact, I think I even recall a built-in pattern editor in some ancient version of the Mac OS. But in today’s world, boring tiled backgrounds have pretty much vanished, to be replaced by gorgeous color photos and even screensavers running as desktop backgrounds. Ah, for the good old days…
Google SketchUp, however, you can easily relive those thrilling days of yesteryear. Download the free version of the program and install it—and give it a test run; it’s an interesting program. In the Finder, control-click on the Google SketchUp program icon (it’s probably in the top-level Applications folder) and choose Show Package Contents from the pop-up menu.
In the new window that opens, navigate into Contents -> Resources. This folder is full of stuff; the item you want is a folder named Textures. Copy it to your user’s Documents folder (or another location on your hard drive) by Option-dragging it out of the Resources window. (The textures only use up 1.9MB of drive space, and by copying them, you’ll be able to keep using them if you later uninstall Google SketchUp.)
Once the folder has copied, open the Desktop panel of the Desktop & Screen Saver System Preferences panel. Click on Choose Folder in the left-hand column, and in the new window that opens, locate the Textures folder you copied earlier, then click Choose. Make sure the pop-up menu at the top of the window is set to Tile, as that will repeat the texture to fill your screen. You can also check the Change picture box if you want to cycle between all the textures.
Not every texture in the folder will necessarily be eye-pleasing, so you might want to delete those you don’t like from the Textures folder. Personally, I find the Stone-squares.jpg texture to be very pleasing; perhaps it appeals to my sense of order. (Those who have seen my desk are presently laughing uncontrollably.)