Add To Calendar feature

We want to put the add to calendar feature we see on many web sites to our website.  We figured out how to add it individually through outlook but it is teadeous doing that for every event indivdually.  Does anyone have a program or idea how to put "add to Clendar" for all events at once? How do airlines do it for every single flight?

It seems like the iCalendar spec is the way to go according to this website here.  It first tells you how to do 1 event at a time, then goes on to show you how to do multiple events at a time.  It looks like you might have to do some heavy coding to do it by hand.  Hopefully someone in the Web Building topic has information on iCalendar-aware event management systems.  What do you use to manage your events now?  Something you programmed yourself or a plugin?  Are you using a content management system that we might be able to assist you in finding a plugin for managing your events?