BMW aren't the only ones with an enormous appetite. A year ago this week, one of Google's fallen angels embarked on her strategic scheme of online world domination. Yahoo!'s new CEO Marissa Mayer quickly demonstrated her gluttonous appetite for devouring companies. Mayer began slow, enjoying Stamped and OnTheAir as appetizers. The acquisitions merely swelled her desire for more, and soon the $10 million Snip.it course was served, followed by a $30 million Summly dish. It wasn't enough, and in between courses, Mayer collected bite-sized companies including GoPollGo, Loki Studios and others. The main course hadn't been served yet. It was the banquet Mayer just couldn't resist. She agonized over her true desire day and night while preparing to receive her $1.1 billion Tumblr indulgence. The gluttonous hunger didn't end there, and now Yahoo! owns 15 more companies than before Mayer's reign. In the first half of 2013, she bought more companies than any other entire year of Yahoo!'s history. For shareholders, the stock certificates no longer attract flies, and a bright new excitement for potential is anew at Yahoo!. At the time of publication, Weinstein had no positions in stocks mentioned.Follow @RobertWeinsteinThis article is commentary by an independent contributor, separate from TheStreet's regular news coverage.