This data visualization is cited by data visualization experts (including Edward Tufte) as one of the best works of all time. It shows an amazing quantity of data in an easily accessible and aesthetically pleasing manner.
Tyler Vigen's 'Spurious Correlations' project is witty and slightly irreverent. It centers on simple graphs of correlations between 2 obviously independent variables (for example, Age of Miss America vs. Murders by steam, hot vapours, and hot objects). It's an important reminder that good data work must underpin good data visualizations.
This amazing interactive graphic helps users see the scientific evidence supporting (or not!) popular health supplements. It contains a massive amounts of data from scientific studies, rendering such information accessible to the layperson.
Unsurprisngly, Twitter is a great place to find folks doing cutting-edge data work. And, as a bonus, they all tweet out each others' stuff, so finding one expert you like can help you easily find others.