Sometimes, for whatever reason, you might need to select a weird block of text that doesn't seem possible with the usual click and drag. For those moments, Redditor whosingsthings points out that Option+Command gives you a a more precise highlighting tool.
When you tap down Option+Command, your icon turns into a cross. Now you can select words and letters in a rectangle, regardless of line location or the word. This only seems to work in plain text tools and the exact use-case for this might be a little rare, but it's a handy tip nonetheless.