Below is a famous map produced by the Facebook team, which shows the connections between their users. Where there are multiple overlapping features, the lines show more brightly, giving a clear indication of feature density.
How can this effect be emulated in ArcMap? For example, is it possible to show individual features with a set transparency, and stack these features with the transparency values accumulating to show where multiple features coincide?
The standard > Display > Transparency option applies to the whole layer equally.
The Facebook example uses light features on a dark background, but I'm also interested in dark features on a light background.