Currently I'm putting circular needles into gallon size zip lock bags, one for each size and any and all lengths in that bag. I figure all the cables have room to spread out & un-coil. I'd like to have a nicer storage system, but every time I look at them I decide I'd rather buy yarn.
I've got a set of Denise interchangables stored in the case they come in; I knit & felted a bag that fits into and it has a zipper pocket on the side for extra cables, etc.
I've got a small amount of individual pieces of Knit Pick's various interchangables stored all together in their own zip lock bag.
I do have a bunch of straights but I don't use them any more. However, I just haven't been able to get rid of them (I'll need whatever I get rid of as soon as I get rid of it!) Not nearly as many as you have so they don't take up much room.
You need to figure out a way to separate that honkin' box full into sizes so you can get a handle of what you have. Maybe just piles spread across the floor for each needle size so you can see just what you've got in each size. While I can see keeping 8", 12" and 14" all size 5 (or whatever) and maybe even keeping 2 or 3 sets of each length (or whatever) you really don't need 20 sets of each length. I'd sort thru and keep any that are particularly pretty or speak to me somehow. If there are no other knitters in the family or anyone who might want some for their sentimental value or any knitter friends, I'd probably 'good will' or some other donation (maybe a local senior center) the majority of the straights.