Mac OS X: 2D Dock in 10.5

I don’t mind the 3D look of the OS X 10.5 dock, but I often prefer the 2D look of the old dock. Plus, I prefer the more-obvious running app indicators from the 2D dock; I find these hard to see in the 3D version. Also, sometimes I just prefer the same look for my dock whether it’s right- or bottom-oriented. Also, hidden apps (⌘H will hide, not minimize, an app’s windows) can be configured to show as transparent icons.

From a terminal:

Credit should be given to macosxhints.com for this.