Embodiments of the present invention are directed to computer-management tools and utilities that allow computer users to save and restore current application-level runtime states of computational environments created by users on computer systems. Certain embodiments of the present invention are particularly directed to time-and-memory efficient state-saving and state-restoring tools and utilities that allow a user to save snapshots of the user's application-level runtime environment, to manage and review stored snapshots, and to subsequently restore the application-level runtime state of a computer system from a previously saved snapshot.