Every holiday season I collect a few new ornaments and carefully pen the year and place that I found them. If they're a gift, I note the giver and the recipient. Giving a holiday ornament as a wedding favor will remind your guests of your special day every year as they unpack their holiday decorations.
Ornaments also make a great guest book. Offer a pile of simple glass ornaments (in your wedding colors, of course!) and metallic pens for signing. You'll give yourself the gift of an instant collection of ornaments for your tree, with notes from your closest family and friends.
How are you using ornaments for your wedding?