Recur Last Version
Today's great software is Recur, you can download Recur free here. but before downloading this program, i recommend you to read the reviews about Recur below :
What Is Recur :
Gregorian calendar date recurrance as described by RRULE in rfc2445. This is an open source java implementation of that rule. When the rule is used, you can ask for all matching dates or given a date find the next/previous occurance.