selectively execute elisp code depending on which machine I'm on

execute-on-machine.el

;; allow customizations per machine
(setq hostname (car (split-string system-name "\\.")))

(defmacro execute-on-machine (machine-name &rest body)
  "Execute BODY only if the machine name matches MACHINE-NAME."
  `(let ((current-machine hostname))
     (when (string-equal current-machine ,machine-name)
       ,@body)))

(setq work-machine "mellotron")
(setq personal-machine "moog")