If you are switching from film to digital, or simply find that you have several film SLR lenses in your possession, I have something for you. There are adapter rings now available that enable old lenses to be used on DSLRs. In my own situation, I happened upon many Olympus OM compatible lenses, and thus bought an adapter for Olympus OM to Canon EOS. These are great for opening up a whole new wardrobe of film lenses to your arsenal.
There are but a few downsides, one being no auto-focus, at least not on most of the cheaper adapters. Exif data like aperture size won’t show up in camera files either. But if you want to breath a new life into your camera setup, or use some old lenses you got from a yard sale down the street, then these adapters are a beautiful accessory for you.