here is what i do. i don't use cards to store my fabric. i use scrap booking bins to store and keep out of sun light and dust. always using your 50% off coupon when purchasing the bins of course :-)
another resource for plastic bins is craigslist. i have found some really nice and tall one and i wash them down good even when they look like new. for my FQs i use the shoe box style bin and usually you can get those for 99 cents at any craft store. hope this helps and good luck with your organization.

I use cardboard boxes. I cut them up with my rotary cutter (I have one cutter marked card board) and a ruler. I cut the bigger size 8.5 x 12" (Why? because I have a ruler that size) for yardage. for fat-quarters 5" square. These sizes fit nicely on my shelves. This way my fabric is setting one the shelves like books. I place them according to color. When I want a particular piece, I can remove it without disturbing the other material. Likewise when I get a new piece I can squeeze on the shelf in its right place. I have been doing this for a long time and had no problems. I figure the fabric stores use cardboard to wrap their material so why not.....I get my boxes from different stores, just make sure they are cleaqd. Most stores are glad to get rid of them. I also save any boxes that come with on line purchases. My husband is addicted to shopping on-line

mat board from frame shop
 

I get scrap mat board form the frame shop. It's acid free so wouldn't damage fabric. It's stiff enought but not too thick. They give it to me for free. If I want larger I do have to buy it, but they give me a good price.

I fold my fabric selvage to selvage and roll it up on my 8 1/2 X 24 ruler. Slide the ruler out and then I put a tag inside with how big this fabric piece is, and then fold it in half. I then stack on the shelves in my wardrobes according to color or theme. I don't have to measure the piece of fabric again, because I have already tagged it, so I know instantly if it is big enough for the project. Fat quarters are stacked on end in plastic drawers, so they are easily identifyable.

I use those foam poster boards at the dollar store!

I use the ruler fold method. Take the fabric folded in half the way it comes off the bolt; fold in half lengthwise again. Now it's about 11" wide. Lay 6x12 ruler on one end and start rolling. When it's all rolled on the ruler, pull the ruler out. No cardboard or foamboard to take up valuable storage space.

I even stand my folded fabric on edge in dresser drawers. There is enough of it that it holds itself upright on edge and I can see every beautiful piece!

I use cereal boxes. Cut the long sides out and trim to the size you want.

I use the same thing.

I use a variety of methods and items to wrap my fabric around depending on what it is and how small a piece. Have found that a good craft knife and ruler are all the go for cutting down the flaps of cardboard boxes.

Go to your local photo/frame shop and see if they have a dump box of left over photo/poster board that goes in the frame and around the picture. The center that is cut out is usually tossed out. It is perfect for wrapping you fabric around. I have a 6' shelf that holds my batik fabrics stored this way. I cut the board 11.5"x8.5". I hope this helps you out.