An interactive dashboard by John Hopkins showing the spread of the coronavirus in real-time is an excellent use of data visualization and often referenced because of its clarity and useless information.
Its interactive feature is effective. The geographical bubble map highlights important data. Overall, the dataviz does a great job of focusing on the most important information, such as the viruses spread from Mainland China to South Korea, Italy, Iran and other parts of the world.
The real-time data makes this visualization especially important.