Mac users interested in Isentry motion detector generally download:
Use iSentry to instantly turn your computer with Web camera into a Internet-connected motion-sensing security system. Just launch iSentry, point your camera to the region you want to monitor, and prepare to receive a video or photo should any motion activity is detected.
With a wide selection of settings, iSentry allows you to schedule the activation time, enable sound alerts, and receive email notifications about the events detected.