Mindtonic

An interesting service to manage mailing lists:

http://www.mailchimp.com/

http://github.com/mandarinsoda/acts_as_chimp/

My research led me here: http://www.francisfish.com/getting_the_number_of_months_between_two_dates_in_rubyrails.htm

This is the method I came up with:

def self.months_between( startdate=Time.now, enddate=Time.now )
  startdate ||= Time.now
  enddate ||= Time.now

  (enddate.month - startdate.month) + 12 * (enddate.year - startdate.year)
end