... Google is buying a seemingly crazy collection of companies ... Take a look at a list of Google’s 144 latest acquisitions and you’ll notice most seem to have little in common. That has a number of technology experts wondering just what the company is up to. This week Google bought SlickLogin, an Israeli startup that uses high-frequency sound waves as the basis of a smart-ID login system. A few weeks ago Google bought Nest, a company that develops thermostats and smoke alarms that are connected to the internet. In December its target was a slew of robotics companies, leading many to jovially question whether or not the company plans to develop an army of robots. Last May, Google purchased a firm called Makani Power that develops airborne wind turbines. In September it acquired a health care company called Calico, which is researching ways to defy aging. The eclectic list goes on. Google has been acquiring companies since 2001, at some points buying one per week. Google has always been much more than a search engine. It’s an advertising company first and foremost - this is where most of its earnings come from. But Google's recent purchases demonstrate the ad-and-search empire may be evolving in a very different direction.