My first attempt on saving space was to ditch the jewel cases. The disks along with the cover sheet were put in an ordinary office folder. One three inch folder would fit almost 40 movies.
Three normal width shelves started to fill up when the collection grew to over 900 items. At the same time the highly inconsistent quality of the CD/DVD sleeves became apparent. Some plastics hardened and stuck to the disks. Because the availability of high quality disk sleeves was poor and the space was running out I decided to switch technique.
Current storage method
A significant search effort produced a set of products for a space efficient storage system. IKEA carries the AVIG box set. They are only available as a set of three so I had to find other uses for the big box.
Each box holds more than a hundred DVD items in Fellowes sleeves. The sleeve has two pockets separated by a soft cloth. This protects the data side of the disk. Also the plastic cover is soft to prevent the disc from sticking to the sleeve. On the top there is a small pocket for an information slip printed from my own database. (The barcode in the picture is the IMDb title number.)
The smaller boxes fit perfectly into my cabinets. In the two shelves previously filled by about 600 DVDs in folders I can now fit about two thousand movies. The lengthy transfer project was well worth it providing me with a easy access movie collection.