3. Flip through your high school yearbooks.
This will be even more fun if you do it with a friend, and not just because she can remind you of who that quiet boy who sat next to you in Algebra II was. "We've found repeatedly that sharing happy memories strengthens relationships and brings you closer to others," says Wildschut. It will also put you in a great mood: Research from another British group, separate from Wildschut's, found that looking at favorite old photos made people feel happier than eating expensive chocolate, having a cocktail, listening to music or watching TV.
4. Introduce your kids to beloved family members—even if they're no longer around.
You can still help your kids get to know relatives they didn't have a chance to meet by looking at keepsakes, family heirlooms and photos, and sharing personal details and funny stories. One way to make this more interactive is to cut out copies of photos of relatives and play a memory game where the kids collect different faces and tell three facts about each person. This will not only help you and your kids feel connected to the family, but Wildschut says that it can also help you feel a little better about losing those family members you were once close to. "Nostalgia does have a tinge of sadness," he says (remember Chevy Chase as Clark Griswold tearing up while watching family films in Christmas Vacation?). "However, most of the folks in our research report that the joy and the warmth they get from thinking about those people predominates."
5. Tackle your family tree.
Building a detailed family tree is a massive project—one that can bring your family together and put you in touch with relatives you didn't know you had. It also offers plenty of safe conversation topics ("Where was great-grandpa born, Dad?"). Many families have traced their history back three or even four centuries using Ancestry.com, which has organized over 7 billion records like marriage certificates, census records, military draft cards and ships' passenger lists. For a subscription fee, you get access to a vast database as well as tools that help you organize and share the information. You could also use your Ancestry.com findings to help direct you to historical societies and libraries in your hometown (or other towns) that might provide additional records. Mary Quimby, an Ancestry.com subscriber whose family tree hobby has become nearly a full-time job, has used the Internet, local archives and graveyards to create a family tree that dates back to 1675, and another for her husband that reaches into the early 1500s. She's found that cemeteries often hold the most rewarding clues: While visiting relatives' tombs in a cemetery in Kentucky, she was surprised to find a long-lost great-great-great-grandmother buried nearby. Quimby suggests shaving cream as an easy way to clear the grime off tombstones and get a better look at inscriptions.
Next: The benefits of rediscovering your hometown