I know I’m not the first to blog about this, but my good pal Brad Wilson (the DotNetGuy) told me about a single command you can execute that turns the dock from this:

(which is visually impressive for a day or two, then it just looks cluttered because of all the eye candy they put in) to the 2D version, which looks like this:

There is still some transparency (it’s not just icons on a black background) but this looks so much cleaner. If you’re interested, open up a terminal window and execute the following command (it may appear on two lines, but it should be entered on a single line):

defaults write com.apple.dock no-glass -boolean YES; killall Dock