De acordo com o comentário anterior de sq33G, o livro que você está descrevendo é quase certamente " Um conto da cidade do tempo " de Diane Wynne Jones;
Panelas com tampas que se transformam em colheres;
The pots, Vivian found, were sort of stuck to the air. She had to give a little pull to get them loose. She discovered that you peeled back the lid, and if you needed a spoon or a fork, the lid shrivelled itself into a spoon or fork shape. Algae soup was not at all pleasant, like salty pond water
Pagando digitalizando os pulsos
“I’m paying,” said Jonathan, and recited a string of numbers. “Yes, but are you in credit?” said the waitress. “Show.” Jonathan pressed one of the buttons on his belt and held his hand out with a row of signs shining on his palm. The waitress looked, nodded, and pressed buttons on the pink matching belt round her pajamas
Existe uma versão completa (e eu assumo copyright) disponível online aqui .