The 35-year old president-CEO of America Online, Mr. Case has brought personality to the cold computer screen, making his service the hottest of the pack while spending a fraction of his rivals' budgets on traditional media advertising.
In April 1993, America Online had 250,000 subscribers. But it expects to hit the 1 million mark this summer.
The company claims it will be the largest commercial on-line service within a year.
Mr. Case provides the service's face.
He sends all new subscribers an electronic welcome letter and replies personally to his e-mail messages.
Subscribers chatting about the service on-line often sprinkle their conversations with casual references to "Steve."
That bond with the audience and word-of-mouth endorsements have clearly played central roles in the service's stratospheric growth, which continued de spite technical problems earlier this year that led some to dub the system America On Hold.
The money-making service's user-friendly graphical interface and its alliances with dozens of information providers, from Time to NBC, also have helped set it apart.
America Online also makes it easy to join, offering trial memberships and distributing free software bundled with computer and science magazines and home PCs.
"Word of mouth is a very powerful channel if you can harness it, and this market, like movies, is unusually influenced by it," says Mr. Case, who held marketing posts at Procter & Gamble Co. and Pizza Hut before founding America Online in 1985.
"It really comes back to having a hot product that people will want to tell their friends about," Mr. Case says.