The wedding tree available on the melangerienyc etsy.com site is a customized chart similar to a family tree that details the relationships of the bride and groom to all of their wedding guests. Great for cocktail hour and receptions, these charts fill guests in on who's a friend from childhood, a neighbor, a family member etc. They also serve as a lovely peices of wedding memorabilia. The colors are fully customizable and its available in a variety of formats including placemats!!
Check them out: http://www.etsy.com/view_listing.php?ref=vl_other_1&listing_id=17027912