Here’s an amazingly simple Tuesday tip concerning Activity Monitor (in the Applications -> Utilities folder). As you may know, you can use Activity Monitor to quit a stuck application, examine CPU usage for all running processes, and look at disk activity, disk usage, and network activity. The top portion of the Activity Monitor window lists running processes along with information on their CPU and memory usage. The bottom portion of the window displays five tabs, each of which displays a tracking graphic for that tab’s activities—CPU usage, system memory, disk activity, disk usage, and network activity.
So here’s the hint—the colors used in the tracking graphic are customizable. Simply click on the color swatch next to the item whose color you’d like to change, and the standard OS X color picker will appear. For instance, to change the color of the Active memory indicator on the System Memory tab, just click on the yellow swatch on the Active line of the display, then choose your preferred color from the color picker.
The only thing to keep in mind is that there’s no Reset Colors menu command—so if you customize a color and think you might want the original back someday, you should save the current color first. One way to do that is to open the color picker, then drag the current color from the space to the right of the magnifying glass down into one of the small boxes at the bottom of the color picker. If you’ve already customized all your colors, however, you can get the originals back by deleting Activity Monitor’s preferences file. Quit Activity Monitor, then navigate to your user’s Library -> Preferences folder. Delete com.apple.ActivityMonitor.plist, relaunch Activity Monitor, and you should be back to the stock colors. (If you’re running OS X 10.5 with Time Machine active, you could use that instead; just restore a version of the preferences file that predates the changes you just made.)