As someone with a lot of digital files (not to mention a slight obsession with making mix CDs for myself and friends) I needed a way to package them right. I was tired of the plastic jewel cases, which forever seem to crack or come apart at the joints and which take up a fair amount of space on the shelves. Thankfully I've found an outlet with all kinds of CD packaging supplies, including the rare cardboard gatefolds I have been so desperately seeking over the years. SleeveTown.com even has cardboard sleeves for LPs, for old time's sake.
Cardboard gatefold CD mailer in white from Sleevetown.com. A package of 50 costs only $16.99.