With the recent delivery of the Rittman Mead Exalytics server [https://www.rittmanmead.com/blog/2012/05/rittman-mead-take-delivery-of-our-exalytics-server/], I have been fortunate enough to be spending time setting it up, most of it at a Linux terminal window. One of the tools I come back to, again and again, is