Where are they now?

Like many of the original "40 under 40," Liemandt -- who appeared on all six of our previous lists -- made his riches in the 1990s technology boom. But unlike many of his dot-com peers, Liemandt's venture -- the software service firm Trilogy -- has had staying power.

That's partly because of his willingness to reinvent. In 2000, when other tech companies famously faltered, Liemandt introduced a new pricing system that allowed clients to pay Trilogy only when its consulting work had an impact on their bottom line. The implicit guarantee kept clients around, and allowed Trilogy to emerge stable when the dot-com bust gave way to a new boom.

NEXT: Jeffrey Citron