Time person of the year Elon Musk tends to hog all the headlines (and a not insignificant portion of the world’s net worth). But we’ve long been just as interested in the fortunes of his chairman, ex-Telstra CFO Robyn Denholm, whose dumping of the telco for the full-time job of wrangling Silicon Valley’s most erratic Twitter personality has made her as rich as Croesus.