Take the old 8-bit Nintendo (NES) games for example. While many of the games featured really nice box art, I just don't care to own the cardboard boxes the games came in. So I'm OK with just buying a loose cart.
One thing about collecting retro games is you have to keep them clean, otherwise every time you insert them into the game system you are just making the connection pins dirtier. I takes a little time to properly clean an NES game or an NES console so my goal is to keep the games as clean as possible. This includes keeping dust off the games. The games originally came with a black dust sleeve and while those work OK, I wanted something better. Stoneagegamer.com came up with some really nice VHS style clamshell cases recently, but being on a tight budget I couldn't afford to house all my NES games in those. Thankfully I found a cheaper solution that works for me. Enter Videogameboxprotectors.com
These cases are made of PET (Polyethylene Terepthalate) which is a better plastic than PVC. They are acid free and ligind free, making them perfect for long term storage. They are 12 mil / 0.3 mm thick and are shipped to you unfolded. Simply fold them together and insert your game!
I had a few of these type cases that I acquired online years ago, but was unable to find them again until recently. These guys offer a variety of sizes to fit just about any retro cartridge. They also offer cases that fit your boxed games too!
Prices are more than reasonable in my opinion. The cases are sold individually or in packs of 10, 25, 50, 75 and on. NES cases for instance are $.80 each, 10 for $7.10 ($.71 ea) or 25 for $15.00 ($.60 ea).
I wanted to case my NES, SNES, Famicom and Super Famicom loose carts, since I don't care to own the boxes (in most cases) for those platforms. My first order recently arrived and I've got to say I love the product. I will be back for more, especially to finish off my NES collection and start off casing my loose Famicom carts as well.
One of the things I like about these cases, especially for SNES and Super Famicom is that it allows me to finally stack my games. With the natural shape of the cartridges they don't stack very well, or stand up on their side. Now that they are encased I can display and organize them on my bookshelf however I see fit.
The standard NES cases also fit Camerica, Color Dreams, Tengen and Wisdom Tree carts.
As you can see the Super Famicom cases are slightly smaller than the SNES cases.
I picked up a few Genesis cases as well hoping they would fit a few loose Mega Drive carts I have...and they fit perfectly!