I have a digital camera with me most of the time. One of the ways I use my camera is for notes. If I take a picture at a certain location--let's say of an ancestor's house--I first take a picture of the street sign. When I add the photos to my computer, they will be in order. The street sign photo will tell me where the house is until I can get notes and tags on the photo.
When I went to the Family History Center yesterday, there were four films waiting for me. When I found the marriage record I was seeking, I took a picture of the film case first:
Now that I am back home and getting ready to add this record to my database, I have the information on the film including the unique 7-digit number. I also capture images of the spine and introductory pages of a book so I know everything I can about the record for input when I get home.
Cameras aren't just for pretty pictures. They're also good for taking notes in a pinch.