Some alternatives to a monetary gift for a wedding are a personalized memento for the couple or something from the couple's registry. A donation can also be made in the couple's name to a charity they value.
If a guest gives a gift to the couple on their wedding day, it is best to stick to the registry that the couple created. If others have purchased the items on the registry already, identify themes within the registry to buy a complementary gift. For example, if the couple registered for several wine related items, buy the couple a bottle of wine, a wine opener or a wine themed gift basket. If the couple likes to travel, luggage is a nice gift. Engraved champagne glasses and a celebratory bottle of champagne is a classic gift.
Personalized gifts are also thoughtful for a wedding. Use a website that creates photo gifts to make a personalized gift starring the couple, for example a photo canvas or throw blanket. A fancy picture frame for the couple to place a wedding photo in is another gift idea. Some stores can engrave a silver wedding frame with the couple's names and wedding date.
If a guest does not want to give cash or a check to the couple directly, he could donate the money to a charity that has special meaning to the newlyweds. For example, if the couple has a beloved pet, a donation to an animal shelter or the ASPCA is appropriate.