Looking for something different from the traditional guestbook? This is a wonderfully creative idea! Provide a calendar instead of a book and ask your guests to sign their names on their birthday. You'll never miss a birthday again! You could also ask married couples to note their own wedding anniversary on the calendar.
Make it a calendar that matches your theme and/or colors (nautical, spring time, birds, etc...). You could even take it one step farther and order a personalized calendar online. Use photos of you and your sweetie for each month; engagement photos, vacation photos, holiday photos, etc... You can also put a special stamp or sticker on your wedding day/anniversary!