For tracking devices, the genre falls into LBS, or Location-Based-Services. LBS devices generally have some type of transceiver (I've developed many; from GPS to WAN-cellular, to RFID and even ZigBee protocols), and then the big kicker: a significant battery for the transceiver. All this adds up to a relatively larger volume than what is depicted in this device shown, which I liken more to a collection of sensory collectors.
It doesn't look like it. I've use the 'Loc8tor' for keeping track of my cats and dogs. It provides directional (arrows) as well as distance (sound) information up to about 600'. The same company has other products that work from further distances, but not as precise.
@pete.cross: That's a very interesting master's thesis ("Control, communication and monitoring of intravaginal drug delivery in dairy cows"). I'd imagine that getting a cat to wear a collar is very simple in comparison.
Ever wanted to see light beyond what's detectable by the human eye? You can with DOLPi - a homemade Raspberry Pi-based polarization camera. You can even use it to detect unseen objects like landmines, IEDs, pollutants, and maybe even UFOs.
A Design News contributor takes on the challenge of building an old-fashioned metric clock that uses French Revolutionary time, which divides the day into decimal units, and shows you how to build your own.
Focus on Fundamentals consists of 45-minute on-line classes that cover a host of technologies. You learn without leaving the comfort of your desk. All classes are taught by subject-matter experts and all are archived. So if you can't attend live, attend at your convenience.