A couple weeks ago I went to my grandmother's house (she is 85) and had a slide show of a trip that she, my mom, and I took back in 1995. Didn't get through all the slides (showed about 200, there are about 50 left to show), but Grandma, Mom, and I had a great time. So did the rest of the family that showed up.
My son wants to take some of his slides to show next time we go. Should be a real good time, and we'll even break out the popcorn.