Skill testing question: how many humans currently living on Earth remember Broadcast.com? Answer: approximately nine. The company was purchased by Yahoo during the First Great Dot Com Boom for the not inconsiderable amount of $5.7 billion in stock and turned Mark Cuban into Dallas Mavericks' owner and also an insufferable rich brat. Man, wasn’t 1999 a gas? But Yahoo’s new president and CEO, the highly respected ex-Google-ite Marissa Mayer, is still buying companies 14 years later. What’s changed, if anything? By RICHARD POPLAK.