diff --git a/Demo/scripts/unbirthday.py b/Demo/scripts/unbirthday.py
new file mode 100755
index 0000000..492b247
--- /dev/null
+++ b/Demo/scripts/unbirthday.py
@@ -0,0 +1,106 @@
+#! /usr/local/bin/python
+
+# Calculate your unbirthday count (see Alice in Wonderland).
+# This is defined as the number of days from your birth until today
+# that weren't your birthday.  (The day you were born is not counted).
+# Leap years make it interesting.
+
+import sys
+import time
+import calendar
+
+def main():
+	# Note that the range checks below also check for bad types,
+	# e.g. 3.14 or ().  However syntactically invalid replies
+	# will raise an exception.
+	if sys.argv[1:]:
+		year = eval(sys.argv[1])
+	else:
+		year = input('In which year were you born? ')
+	if year in range(100):
+		print 'I\'ll assume that by', year,
+		year = year + 1900
+		print 'you mean', year, 'and not the arly Christian era'
+	elif year not in range(1850, 2000):
+		print 'It\'s hard to believe you were born in', year
+		return
+	#
+	if sys.argv[2:]:
+		month = eval(sys.argv[2])
+	else:
+		month = input('And in which month? (1-12) ')
+	if month not in range(1, 13):
+		print 'There is no month numbered', month
+		return
+	#
+	if sys.argv[3:]:
+		day = eval(sys.argv[3])
+	else:
+		day = input('And on what day of that month? (1-31) ')
+	if month == 2 and calendar.isleap(year):
+		maxday = 29
+	else:
+		maxday = calendar.mdays[month]
+	if day not in range(1, maxday+1):
+		print 'There are no', day, 'days in that month!'
+		return
+	#
+	bdaytuple = (year, month, day)
+	bdaydate = mkdate(bdaytuple)
+	print 'You were born on', format(bdaytuple)
+	#
+	todaytuple = time.localtime(time.time())[:3]
+	todaydate = mkdate(todaytuple)
+	print 'Today is', format(todaytuple)
+	#
+	if bdaytuple > todaytuple:
+		print 'You are a time traveler.  Go back to the future!'
+		return
+	#
+	if bdaytuple == todaytuple:
+		print 'You were born today.  Have a nice life!'
+		return
+	#
+	days = todaydate - bdaydate
+	print 'You have lived', days, 'days'
+	#
+	age = 0
+	for y in range(year, todaytuple[0] + 1):
+		if bdaytuple < (y, month, day) <= todaytuple:
+			age = age + 1
+	#
+	print 'You are', age, 'years old'
+	#
+	if todaytuple[1:] == bdaytuple[1:]:
+		print 'Congratulations!  Today is your', nth(age), 'birthday'
+		print 'Yesterday was your',
+	else:
+		print 'Today is your',
+	print nth(days - age), 'unbirthday'
+
+def format((year, month, day)):
+	return '%d %s %d' % (day, calendar.month_name[month], year)
+
+def nth(n):
+	if n == 1: return '1st'
+	if n == 2: return '2nd'
+	if n == 3: return '3rd'
+	return '%dth' % n
+
+def mkdate((year, month, day)):
+	# Januari 1st, in 0 A.D. is arbitrarily defined to be day 1,
+	# even though that day never actually existed and the calendar
+	# was different then...
+	days = year*365			# years, roughly
+	days = days + (year+3)/4	# plus leap years, roughly
+	days = days - (year+99)/100	# minus non-leap years every century
+	days = days + (year+399)/400	# plus leap years every 4 centirues
+	for i in range(1, month):
+		if i == 2 and calendar.isleap(year):
+			days = days + 29
+		else:
+			days = days + calendar.mdays[i]
+	days = days + day
+	return days
+
+main()