There’s no way around it: America’s getting older.

As the Baby Boomer generation heads toward retirement, the number of Americans over the age of 65 is expected to hit 69 million people by 2030. That represents 20% of the U.S. population, up from today’s share of 13%.

It comes as little surprise, then, that finding ways to extend a healthy life has become big business, attracting many tens of millions in investment dollars from the likes of Google GOOG and numerous biotechnology companies.

In Silicon Valley, finding new ways to dramatically extend human longevity has become almost an obsession. Oracle Co-founder Larry Ellison has called mortality “incomprehensible;” Google Co-founder Sergey Brin has said he hopes to someday “cure death;” and Russian entrepreneur Dmitry Itskov said he plans to live to 10,000. Some tech titans are donating millions or personally leading the research into longevity solutions. Here’s a look at six of those people and their pet projects: