They may add a bit to the cost of your wedding stationery suite, but if you're having a destination wedding or nuptials that are more of a multiday celebration, itinerary cards can save you -- or your parents --- a fortune in the long run.
These cards act as miniature event calendars by listing the locations, dates and times of all wedding-related happenings. Included response cards let you know in advance which events your guests will and will not be attending, so you don't have to reserve a boat for 200 people on the off chance that everyone would like to go deep-sea fishing. Your guests will also appreciate knowing the events to which they'll be treated and which ones they'll have to pay for themselves.
Your itinerary cards don't have to be too detailed. You'll want to list the location and time of the rehearsal, rehearsal dinner, ceremony, reception and send-off brunch (that is, if you're having all those events). And if just a portion of your guests will be invited to those events, don't send the cards to everyone! You can have a separate set printed for your wedding party and family, or include an insert with official wedding business for those who have roles to fill and places to be.