Protect posts based on user id

So here is my pet peeve with all blogging platfroms that I’ve tried and used. I have not been able to find a platform that will allow me to have users register on my site, and then restrict access to individual posts based on who the user is.

For example let’s say I have WordPress installed and 20 people that have registered. I may have one post where I only want Sally, John, Rich, and Holly to see. Then another post where only Sally and Holly can see.

I looked through the forum as best I could, and the plugins, but could not find such a hack or plugin. Does anyone know of a plugin or way I may be able to do this whether it be with WP or any other blogging platform?