During exams, some of my friends put Saran Wrap over their plates before a meal to avoid having to wash dishes afterwards. What should be invented is a type of spray-on non-toxic invisible wrap that clings to dishes so that you can eat off them. After your meal, remove the wrap and throw it out and put your dishes back in the cupboard without washing them. It would be a bonus if the wrap was biodegradable as it would save a lot of energy.