Relax everybody, unlike its antonymous quadrocopter cousins, this six-rotor drone isn't here to kill, only to count plants. Researchers from Oregon State University are hanging cameras from reasonably-priced RC aircraft to help nurseries track inventory -- a task often performed by workers wandering the orchards and keeping tally by hand. Image analysis software automates the process and, with the addition of other sensors (such as infrared), it could one day be used to spot irrigation problems, identify diseased trees, and estimate crop yield. The machines themselves can climb to over 80 feet and stay aloft for up to 40 minutes while hauling 5-pounds