1. Using a copy-paste manager to get more than 1 buffer (like Keyboard Maestro, but there are free ones)
2. In a lot of editors (not vi), if you need to get back to the point of your last edit (because you scrolled away) use the keyboard shortcuts for UNDO, REDO. So in a lot of editors, CTRL-Z, SHIFT-CTRL-Z -- this jumps you right back to where you last changed something.