This story demonstrates that you can improvise a formal dining table almost everywhere as long as you can sit people. These are pictures taken at a formal luncheon for a dozen people that was staged aboard the Brooklyn-bound L train. It must have been fun to do as an adventure.
As you can see, the food was fancy. They even serve a soup. The key was to use plates and bowls that limit the chance of a spill. The table trays also have a hole to keep the glass in place while the train was moving.
The set up is a concept that is worth stealing from. It would not be too hard to make your own table trays for when you invite more people that your dining table can sit. What you need are ready-made tablets cut to fit your space and to figure out how they will be held in place. The solution depends on where you will hang them or if you prefer to use legs.
+ Aboard the L-train, Luncheon is served – photos by Yana Paskova for The New York Times