A new product from Back2Basix: 40k coherency trays. The idea behind them is simple enough: not only do these trays help with moving large numbers of ground troops in a quick and simple manner (especially if you're a tyranid horde player for instance), but they also spread out your troops to a maximum coherency. The obvious reason to do this is to minimize damage from incoming template and blast weaponry. But if the infantry need to leave the tray to get inside a building, they can also do that readily as well. Different trays are available (5, 10 or individual models) which makes for maximum flexibility. Hence if a fixed formation doesn't appeal, an equal number of individual trays would be perfect.
Is this a legal play aid? Well, I can't see any direct rules against them (unless I'm missing something), and they'll help speed up the movement phase for horde players. I don't think I'd be bothered to play against such innovations, as it is what good players aim (and mostly succeed) to do anyway. And moreover, the trays can readily be painted up to the same quality as fantasy movement tray analogues which would probably look great. I'm tempted to get a few and see what they're like to play with.