The invention features an apparatus for delivering mechanical energy to an expanse of skin, wherein the apparatus includes: (a) a skin-contactable element having a skin-contactable surface, wherein the skin-contactable element includes an agent selected from the group consisting of a benefit agent, an apparatus-enhancing agent, and combinations thereof; (b) a motor; and (c) a transfer member for transferring mechanical energy from the motor to the skin-contactable element in order to provide periodic motion to the skin-contactable surface; wherein the agent is configured to release from the skin contactable element to the expanse of skin upon contacting the skin-contactable surface with the expanse of skin.