Custom inspector icon vs component asset icon

Just for the fun of it: I went into inspector debug mode and changed the icon of my script asset. Naturally, it shows up in the project view and on the component inspector. However, I've noticed that Unity uses different icons for the two default C# icons and also, that my custom icons look rather bad when shrunk down to fit the inspector. Would I be able to use two different icons as well via my custom editor/inspector?