Here's an interesting concept: UK-based design student Ryan Jongwoo Choi's anti-dish-dropping Magic Tray concept. Choi wanted to design a tray that would make it easier for restaurant servers to carry dishes, bowls and plates with little danger of spilling them. The Magic Tray thus has interior magnets, as do the dishes and vessels themselves; hence everything sticks fast to the tray.
Choi's design cleverly calls for springs inside the tray that, when the tray is set down, release the magnets from the underside of the top surface of the tray. Thus the dishes and such can then be removed.
There are a couple of potential issues, like with the design calling for the embedding of magnets in the undersides of the dishes themselves. In your average restaurant's kitchen, the line cooks are usually separated from the servers by a row of pass-through stainless steel shelves. The cooks place the finished dishes onto the shelves, and the server retrieves them. If those shelves are ferritic stainless steel, there's going to be magnetic attraction, and yanking a dish strongly enough to break the attraction could conceivably cause a problem. If the shelves are austenitic (non-magnetic) stainless, no problem at all.
The other thing I got to thinking was that even if the vessels remained on a tilted tray, the real danger is the contents of those vessels spilling out of them.
Still, I think the idea has merit and I'd love to play around with one to test it out. Oh wait a second, no I wouldn't. I hated working in restaurants. But here's the concept vid: