How do I become a billionaire? Can someone write an easy-to-follow guide for that?
Carlos Slim and/or Larry Ellison are low-profile? Maybe yes today because of their age but I must have been reading articles and seeing news from a parallel universe then because they were being mentioned pretty much everywhere on a regular basis just some 10 years ago. Slim was a solid #1 for years on the Forbes billionaires list too.
Sheldon Adelson is also a low-profile billionaire (although not tech-related)... because he's dead.
Larry may be 'low profile' these days however decades ago he enjoyed disrupting the software markets and (if I recall correctly) was behind the creation of 'Open Office' (MS office clone) and released it to the wild as open source.