I should mention that Crossfilter and Cube are pretty dead - Mike Bostock, who originally wrote them, has left Square, and apparently they don't use them intern

I should mention that Crossfilter and Cube are pretty dead - Mike Bostock, who originally wrote them, has left Square, and apparently they don't use them internally anymore. As somebody else mentioned, DC.js (http://dc-js.github.io/dc.js/ http://dc-js.github.io/dc.js/) is (one) replacement, at least for Crossfilter.