It's said necessity is the mother of invention. About 15 years ago, Dr Gernot Heiser, from Data 61, looked ahead and, despite being fit and healthy, could foresee a day when he might need an implanted, life-supporting device such as a pacemaker. And he didn't like the idea the it might be attacked remotely. So, he set out to build a trustworthy computing platform that could not be hacked.