https://www.slideshare.net/gtmarketing8688/data-visualization-inspiration-analysis-to-insights-to-action-faster

I found this visualization to be very simple but very effective in communicating the core message. The first visualization uses a pie to display the list of countries with the highest consumption of oil. All countries are not presented at first. Only the one with bigger circles is shown with the label of the corresponding name of the nation. But when someone hovers the mouse on smaller circles it provides with more details.