How do you clean off burned on grease on outside of skillet without harming the surface?

Well, darling, grab some baking soda and water to make a paste, then scrub that burnt grease off with a good ol' sponge. If that doesn't cut it, try a sprinkle of salt and a splash of vinegar for some extra muscle. Just make sure to rinse it well afterwards, unless you want your next meal to taste like a science experiment gone wrong.