Unplug the mouse from the right side of your keyboard and into the left (or vice versa). Use it. Not just for 30 seconds but all day long. Shocking how difficult this, like mirror writing. Start by feeling like you’re stumbling across the surface of the moon. Then move on to more subtle annoyances, like wishing scrollbars were on the other side of windows. Overall, it’s a realization of just how lopsided your brain/body patterns have become with time (I’ll wager this experiment is harder the longer you’ve been using computers).
Creeping pain in forearms/elbows has me looking for ways to minimize onset of RSI difficulties.