Charles Simonyi created some of the most widely used computer-software programs on Earth. Now he's ready to take on the next frontier: space.

Simonyi, formerly a top researcher at Microsoft and co-founder of Intentional Software in Bellevue, has booked a seat aboard a Russian rocket for a flight to the International Space Station as early as next year.

He could become the world's fifth space tourist, following American businessmen Dennis Tito and Greg Olsen and South African entrepreneur Mark Shuttleworth, who have made the trip, as well as Japanese businessman Daisuke Enomoto, who is preparing to take part in a space flight in September.

The trips for private space explorers are organized by Space Adventures, a Virginia company that works with the cash-strapped Russian space agency, which has turned to space tourism to generate money.

Space tourists pay to occupy a "taxi seat" aboard the flight as crews and vehicles are rotated every six months. They take off with a new two-person crew, spend a week at the space station orbiting 220 miles above Earth and then return with an outgoing crew. The permanent crew members of the space station are Russian and American astronauts.

Simonyi, 57, promises to be no ordinary passenger. Born in Hungary, he speaks and reads Russian, he's a trained pilot with a keen interest in aerospace technology, and he's already thinking about how to use his engineering know-how to assist the space station's work.

"I'm technically capable, so I'm sure I can make myself useful," he said in an interview. And, he added, "I come cheap."

But the ticket price won't be. While Simonyi may provide his labor free of charge, the trip will cost him $20 million. Last year Forbes magazine estimated Simonyi's wealth at $1 billion.

Simonyi earned his fortune over more than two decades at Microsoft, where he led teams that developed Word, Excel and other software applications that have become ubiquitous around the world. Before that he worked at Xerox's famed Palo Alto Research Center (PARC) in the 1970s.

In 2002, Simonyi left Microsoft to launch Intentional Software, which is developing new kinds of tools for software programmers.

He has been active in funding Seattle arts and sciences; his philanthropy includes a $10 million grant to the Seattle Symphony and a $3 million gift to the Seattle Central Library downtown, where his name is on the fifth-floor Mixing Chamber.

To learn about space flight, Simonyi traveled to remote Kazakhstan two years ago to see the launch of the Russian Soyuz rocket. He met retired Russian cosmonaut Yuri Usachev, who logged more than 670 days in space, and learned about his experiences.

"I think it's a unique opportunity," he said. "I might have dreamed about it, but I never thought it would be realistic."

He also sought advice from American astronaut Neil Armstrong, the first man to set foot on the moon, whom he met in Seattle during a tribute to the Apollo 13 mission.

"I want to go all the way in terms of learning everything," he said.

With typical Microsoft gusto, the man who helped invent productivity software already has some thoughts about how to improve things such as the spacecraft's checklist and manuals, and taking inventory at the space station.

Simonyi, who has done some preliminary training and passed his medical examination, said one of his goals for the flight is to study the different Russian and American engineering approaches.

That might sound surprising coming from someone who grew up in Hungary during the Cold War.

"I'm in awe of Russia in its capabilities," he said. "It's the Soviets I couldn't stand."

Simonyi also wants to play a role in the effort to commercialize space travel, which he thinks will help advance the technology.

"We all think that when you listen to 'Star Trek' and they say it's the final frontier, how are you going to conquer space if you're not taking steps to get more kinds of people into space? This is a small step."

Kristi Heim: 206-464-2718 or kheim@seattletimes.com