With a keen eyed suggestion from my girlfriend, I grabbed this at Target today.
It snaps together, and can be expanded, though too much and it would be unwieldy I would think. The boxes are fairly large, and can even fit the model I was worried about, the Thunderwolf waving his hammers around over his head. It could be a hard fit for taller models and maybe eldar tanks, things with flying stands etc.
As you can see it fits 4 rhinos easily, with room for all the guys in them, you could probably get 2 land raiders in there with plenty of room to spare.
Here is a shot of the box closed, it would be quite the good carrier from the car to the table, but for storage and long transportation, a foam case is a lot safer. But to carry around at a tournament(if displays don't matter) it would be a great case.
One last product plug, here is a shot of my custom dice bag from Dragon Chow. It's flat on the bottom to stand up on the table, hell I might use it for wargaming too as I do that more often. It's orange on the inside and has PBR on the outside, the opposite of me most days. The ONLY complaint is that she couldn't get University of Texas Burnt Orange fabric, but that is a minor quibble, she even asked me about it and showed me the current mottled orange that is in there. Now that is customer service.
Lyndsay ( she's Canadian, how exotic) makes them by hand, and even gets you custom fabric if need be, the PBR cans she designed and had made herself. It was $17 including custom fabric for a hand made dice bag( could be more depending on fabric). That's even cheaper than the bottle of Crown Royal (also Canadian, I see a theme), that it takes to get a bag that way. As far as I can tell she can make anything. You can also find her on Twitter as @GeekyLyndsay.