According to The Knot the tradition of carrying something old comes from an old English rhyme: “Something Olde, Something New, Something Borrowed, Something Blue, and a Sixpence in your Shoe.” Specifically, carrying something old represents a bridge between the past and the future. Here is a “something old” idea:
Jewelry: I have a bracelet that belonged to my great-grandmother. She got it back in the 1920's from the elevator operator in her building who was smitten with her. A piece of jewelry with an interesting past, whether from someone you know or from the local consignment shop, adds a nice sense of nostalgia to your wedding day.