Repository pattern WITHOUT mapping?

I was just wondering (surprised?) if anybody uses the repository pattern with CLR objects in their applications … without an ORM? What I mean is, does anybody let the repository implementations do the mapping, rather than rely on a third-party framework?

I had this idea of doing just that. Mapping fields for CRUD operations, for the given db type, within the repository implementation specific for that type of db. Association collections would be simple list<t> that would by empty unless filled by a service class.