\$$\mathbf{Cat}\$$ is something like a categorified topos.

After all, since the category \$$\mathbf{Set}\$$ is the prototypical topos and since a \$$\mathbf{Set}\$$-category is another name for a category, then \$$\mathbf{Cat}\$$ the category of categories is by another name the \$$\mathbf{Set}\$$-category of \$$\mathbf{Set}\$$-categories.

In fact, I wouldn't be surprised if all toposes can be enriched like the category \$$\mathbf{Set}\$$.