There are two types of people: those who set on one font/color theme for the rest of their life and those like me, who constantly tweak their setup. Not that it helps productivity, but hey – RMS created
.emacs for a reason!
Since typing in font names over and over again is a pain, I’ve created a neat function that can be called interactively to rotate between various programming-friendly fonts installed in the system. The list of fonts is partly mine, partly borrowed from Programming Fonts (which is awesome on its own). This allows a very quick way to see how one’s code looks with different fonts (and make a final decision for the next 3 weeks or so).