Richard Duvall, a pioneer of online banking and a co-founder of Egg, has died aged 44, following a short battle with cancer.
Duvall, who set up the online bank in 1999, had been more recently working on Zopa, an online loans exchange for people who do not use conventional banks.
The business world has been paying tribute to Duvall, who was once described by Bill Gates as "one of the most dynamic people I have ever met".
Simon Woodroffe, founder of Yo! Sushi, describes him as "a giant of his generation. The entrepreneurial world looked up to him as an intellect, an achiever and a human being. More than anyone of our generation, he could see a long way into the future and I will miss that connection".
Mike Harris, a former ceo of Egg who hired Duvall at the Prudential in 1995, describes him as a "great creative force".
Phillip Cullum, deputy chief executive of the National Consumer Council, adds: "His loss will be felt by many people on a personal level. On a professional basis, his passion for consumers will be greatly missed."
Duvall led the team that developed the Egg concept at the Prudential, and later became its first chief marketing officer, responsible for creating and launching the brand.
Zopa will continue to be led in the UK by chief operating officer James Alexander, and it says it will carry on working towards a launch in the US.