Red and white is the original iCal icon color. Let's change it.
File with icns Format
iCal icon is stored in the file App-empty.icns. This file full-path is :
Macintosh HD ▸ Applications ▸ iCal ▸ Contents ▸ Resources
Adjust Color Using Preview
You are recommended to back up the original icon before doing some changes in the icon. Now, open the App-empty.icns with Preview. Next, you may use the new Preview tools Adjust Color and make the adjustments like below :

TIFF Format
Next step is to save the file in TIFF Format. Now you should get App-empty.tiff. However, the one that is needed by iCal is in the format icns. Therefore, you should change the file extension to .icns.

Relaunch iCal
The final step, you should relaunch your ical. Finally, you will get brand new look of your iCal.

Attachment
Original iCal
Burned iCal
Gloomy iCal

Note : Change the filename to Apple-empty.icns and copy it inside the path :
Macintosh HD ▸ Applications ▸ iCal ▸ Contents ▸ Resources
1 COMMENTS (RSS)
jonathan graves
December 9th, 2007 Time: 11:11 AM
Nice. If you do some juggling between Illustrator and Preview/.png and .icns, you can change the whole thing. Still haven't figured out the numbers, though. It seems to generate the icon depending on the day instead of selecting from a library of them. Weird.