If you've got a lot of ND and ND grad filters like I have, then you're probably making do with the (cloth) Lee Filter case. I have the excellent leather access case - see below - (but it's rather heavy out in the field and it only stores six filters). It is a great filter case, sturdy, and has amazingly quick access to my filters. I've had no complaints using it, except perhaps the weight of it, and the fact that I could do with a few more slots for a couple of more filters.
I personally detest the cloth case made by Lee. The zip makes getting access to the filters cumbersome, and once i've got the case open (like a book - using both hands), I have to go through each page in the holder to guess which filter is in each cloth cover. If I'm using the ND filters - which are square, they are buried deep within one of the cloth pages, and it can take a while to fish them out.
I hate faffing (a UK term for fidgeting).
Anything that causes me any delay in making the images I'm seeing open up in front of me - must go. I've discarded a lot of equipment over the years because it's either too cumbersome, or simply it gets in the way. You'd be surprised how much stuff isn't made to do the job it's advertised to do. Well, the Lee case isn't quite in that territory - it works, but it's a little fidgety for me.
Each month on my workshops, I get folks coming along with the latest and greatest cameras, tripods and bags. The past few months I've started to see the Kinesis Large Grad Filter Pouch on my trips and I've just placed an order for one today (Kinesis have a problem with their web site which means you have to email them to buy anything from them if you are not in the US - get this sorted out Kinesis! You'll be losing a lot of trade from this!).
The pouch as you can see is like a mini filing cabinet. I like how the filters are stored sideways, and there are some nice velcro labels attached to each section so you can find the right filter quickly. Access is a breeze. No horrible zip to undo, no filters falling out all over the place either. The filters are tightly packed together, and there's ample room in there for quite a number of them too.
I can't stress how important 'process' is to my photography. I have all my gear organised. I put things away in the places they were before I used them, because it means I don't have to spend time hunting (faffing). Likewise, I dumped the Lee cloth case because it's just a pain to use. I never zip it up because it takes a lot of time to unzip it round three edges of the case. The Kinesis has been designed with thought and care. It doesn't just store your filters - it has been put together to give you quick and easy (read organised) access.
Highly recommended.