I discovered an interesting list of days to fly the Scottish flag on the Daughters of Scotia's web site:

DATES TO REMEMBER: The Saltire should be flown on the following Scottish Anniversaries:
January 1 - New Year's Day

January 25 -Burns Day

April 6 - Declaration of Arbroath Day

June 24 - Bannockburn Day

August 23 - Wallace Day

November 30 - St. Andrew's Day

-- http://www.daughtersofscotia.org/flag.html
This is a really great thread, and I hope we'll see some more additions -- I'm planning on putting a calendar of days to wear the kilt & fly the flag in our St. Andrew's Society's newsletter.