This interactive application from The Wall Street Journal provides an historical view into the national unemployment rate since 1948. Provided with data from the Bureau of Labor Statistics the application does a nice job in immediate insight.
The data is organized in a table with the years from 1942–2009 as column headers and the months of the year are shown as the rows. The cells are filled with a color scheme ranging from red (high jobless rate) to green (low jobless rate). This gives an easy to understand heatmap-like overview. The interaction model is very basic and only provides a tooltip functionality and some additional filter for recessions. It would have been nice to implement some information with higher granularity. But the overall visual design is clean and easy to read.
View the interactive table on The Wall Street Journal