The control of passive dynamic systems remains a challenging problem in the field of robotics, and insights from their study can inform everything from dynamic behaviors on actuated robots to robotic assistive devices. In this work, we explore the use of flat actuated environments for realizing passive dynamic balancing and locomotion. Specifically, we utilize a novel omnidirectional actuated floor to dynamically stabilize two robotic systems. We begin with an inverted pendulum to demonstrate the ability to control a passive system through an active environment. We then consider a passive bipedal robot wherein dynamically stable periodic walking gaits are generated through an optimization that leverages the actuated floor. The end result is the ability to demonstrate passive dynamic walking experimentally through the use of actuated environments.