I didn't think a second screen would change how I work until I actually used one. For the last few weeks, I've been running the Plugable USB-C Portable Monitor alongside my laptop, and it's quietly become the accessory I'm most annoyed to leave at home.
Not because it's flashy, but because it solves a problem I'd stopped noticing I had: everything I do, from research with three tabs open to editing a draft while a spreadsheet sits in the background, is easier with two screens instead of one.