Synopsis: You have an big ugly block of wrapped text in a cell and want to break it up with line spacing to make it easier to read. You could just keep tapping your space bar, but your changes won’t hold if you ever change cell width. This solution is so simple.
Step 1: Put cursor in text where you want a break.
Step 2: Hold ALT
Step 3: Hit ENTER
Step 4: Repeat where needed.
Step 5: Done.