Lost your computer? The one who has it right now may just boot it up to see what it does, and then prey comes in. In standalone mode it every now and then checkes a url. If the url returns 404 (not found), prey will start e-mailing via the configured mail server to a designated e-mail adres with location data, a full screenshot, a webcam pic and a few bits of extra data. That might be just enough to find that person and claim your laptop back.