Screenshot of Exemplar
Springer has an interesting tool that lets you search for a pattern and see its distribution. When you search for a term it allows you to see distribution over time in the upper left, then distribution over disciplinary categories. It also shows a KWIC (Keyword in Context.) See Springer Exemplar: Search Results for Interactivity. The design is clean and easy to explore, but the content seems to be only recent materials in Springer journals.