~/Library/Preferences/com.apple.finder.plistSearch for 'icnv' and you should find a section that looks like this:
<key>icnv</key>Change the "0" below "BackgroundFlags" to a "1" (and save the change!) and then either logout and login or relaunch the Finder. When you do so, the image you place in the Global View Options will be tiled in the background of the Finder windows.
<dict>
... lines not shown ...
<key>BackgroundFlags</key>
<integer>0</integer>
... lines not shown ...
</dict>
Sebastien
[Editor's note: This is distinct from the previous tip that discussed tiling desktop images, although closely related! In order to see the keys discussed, first go to the Finder, open a new Finder window, set it to view by icon, and specify a background image. You should now have the BackgroundFlags key in the com.apple.finder.plist file.]

