Card catalogs are still used in many archives and libraries, especially when the cost to digitize them in either time or money is prohibitive. I visited the National Air and Space museum archives once to access a special collection, and one of the main ways they still found documents in this collection was through an old card catalog, though they did have a digital database of most of the information in the card catalog. I only needed to use the digital database but I did also locate one document I was looking for via the card catalog to see how the collection was organized originally. I think card catalogs will continue to be used for certain special collections for a long time.
