On April 9, at a remote launchpad on the plains of Kazakhstan, a ground controller will finish his countdown; a Soyuz rocket will fire; and Charles Simonyi--Microsoft's former chief architect, the tutelary genius behind its most famous applications, the inventor of the method of writing code that the company's programmers have used for 25 years, and now the proponent of an ambitious project to reprogram software--will begin his ascent into space.

Snug in a Russian space suit, feeling four Gs pressing him down into a form-fitting molded seat liner, the 58-year-old billionaire will become the fifth space tourist to visit the International Space Station. The journey, which will cost Simonyi around $20 million, will fulfill his dream of becoming a "nerd in space" (to borrow one name he chose for the website that documents his extraterrestrial adventure: www.nerdinspace.com). It will also give him an opportunity to view our planet from above and beyond.