Good list. A few more for me: * Implementation/header pairs in C++ * Language REPLs (e.g., Python) * Quick calculations in Calc while coding *

Good list. A few more for me: * Implementation/header pairs in C++ * Language REPLs (e.g., Python) * Quick calculations in Calc while coding * Checking dates on the calendar * Magit status * Diff buffers (especially diff-buffer-with-file) * Listing neighboring files with dired * Notes on a code base/task in an Org mode file