I have a 6-year-old big and expensive scanner that I have lost the cabling for. Somewhere on my to-do list is to replace the cable, and scan thousands of old pictures I have in various boxes. It's a task I never get around to, because I know that completing the project will take me something like 20 to 30 hours, total. And I just don't have that kind of time. If I were to do the "scanning" with my digital camera, however, it would take a fraction of the time -- maybe as little as three hours -- and the quality could even be higher.
Scanners are just digital cameras anyway. However, they do four things better than digital cameras: 1) they hold pictures very flat; 2) they get the lighting just right; 3) they eliminate the possibility of glare; and 4) they don't bend or warp pictures.
With a little planning, you can do all this as well.
The easiest part is holding photographs flat. A little tape on the very edges might work, as long as the pictures aren't too fragile. You might instead use heavy objects along the very edges.
Harder to get right is the lighting. Indirect sunlight is best. Outside in the shade, or indoors in the middle of the day near a window will work. I don't recommend a flash. And make sure you watch out for glare.
To make sure your pictures aren't "bent," or "warped" by your camera's wide angle lense, don't get too close. Doing so requires the use of your camera's wide angle setting. It's better to get four or five feet away and zoom in. The pictures will be flatter.
Use a tripod.
Once you've taken the pictures, open them in your photo editing software, crop out the edges, color correct, and voila! -- "scanned" photos in a fraction of the time it would have taken you with a scanner.
Once you get used to using your camera as a scanner, you might find all kinds of new uses for your handheld "scanner." Take pictures of business cards and documents, "capture" white boards during meetings or class for later study. Take pictures of signs, personal property (in case it's stolen) -- anything you want to remember or keep.
Scanners became the rage way back before digital cameras. Now we have spectacularly good, low-cost digital cameras that take super high-quality pictures -- not just of people and landscapes, but photos and documents, too.
Go ahead. Kill your scanner!