When I have a really bad cold and I blow my nose too much with my Kleenex, the skin on my nose, the top of my lip and lips get super dry and flaky. To the point it's painful because I've rubbed the skin raw. The only thing that helps is Vaseline petroleum jelly. Before I go to bed I apply a thick amount of this all over my raw skin, and by the next day my skin is back to normal.
To moisturize my unpolished nails (including toenails), I use a tiny bit of Vaseline after showering. During the shower nails absorb moisture. Vaseline seals in the moisture so that nails are hydrated. It's important to massage in the Vaseline as soon as possible after showering, so that the nails don't dry unprotected.