Scenario:  A list contains items which have a recurring date.  Anniversary, birthday, things like that.  We want to calculate how many days remain until the next occurrence of that event.

Solution:  Create a calculated column to calculate the number of days from today until the next occurrence.  But today isn’t available in a calculated column, you say?  Bah…Head on over to Mark Kruger’s blog for a quick work around to be able to use Today in a calculation.  Cool. 

Anyway, once you do that, all you need is the calculation (DOB is my column for, well, date of birth):
=DATE(IF(OR(MONTH(DOB)<MONTH(Today), AND(MONTH(DOB)=MONTH(Today), DAY(DOB)<DAY(Today))),YEAR(Today)+1,YEAR(Today)), MONTH(DOB), DAY(DOB))-Today

This Today workaround really opens some doors that were previously closed.  Thanks Mark!