Say you have some dusty old reels on 8 or 16mm film, home movies sitting in a box at the back of a shelf. You’re not even sure what’s on there -- your grandfather’s trip to Europe? Your aunt’s wedding reception? -- as the labels have long curled up and fallen off, and besides, you don’t have a projector to watch them.

The people behind International Home Movie Day want to change all that. On the second Saturday each August, they organize the most D.I.Y. of film festivals: In cities all over the world (58 in 2007, the event's fifth year), you're invited to dig out an old film and bring it to participating theaters so that small-gauge film experts -- rabid about preserving these precious and increasingly discarded peeks into human history -- can inspect it, project it to the audience and even teach you to how to convert and preserve it. It's free, and anyone can bring in films (or just come and watch).