These are a few Add-In files you can download and use in your Calcium installation.

• United States Holidays (includes 2007 DST changes)
• Jewish Holidays (through 2010)
• Jewish Dates (e.g. 22nd of Elul, 5768; through 2010)

• Moon Phases
• Moon Phases w/images
  For this one, you'll also need some image files; the Add-In file looks for them in a directory called "images/moon" off your document root. Get the 4 images in a zip file, or a tar.gz file
• Birthdays of Famous People

Calcium supports Add-Ins in the Internet standard iCalendar format. You can find many other interesting iCalendar files on the Internet, at sites such as:

• Icalshare.com, which claims to be "the largest directory of shareable calendars on the web."
• iCalendar Holiday files from Mozilla.org
• Apple Computer's iCalendar Library