Don’t toss your old Phillips head screwdrivers just because the tips are battered. Restore them instead.
Tighten a rotary grindstone with good 90-degree corners in an electric drill and hold the drill in a vise or handscrew on your worktable. Turn on the drill, lock it in the “on” position so you can hold the screwdriver with both hands, and use it to smooth off the four nicked and battered fins. Use the 90-degree corners on the grindstone to resurface the original angles on the tip. If the screwdriver tip is a real mess, grind off 1/4 in. and then regrind the “valleys” between the fins. Let the grindstone rotate into the metal—toward you—for best control. As always, wear eye protection.