Fear and Coding on the StartupBus: Wired.com reporter Keith Axline was embedded on a StartupBus bound for the South by Southwest conference in Austin, Texas. It was one of six such buses filled with coders competing to turn bright ideas into startup prototypes during the 48-hour road trip. The buses have arrived at SXSW, but the journey continues.

AUSTIN, Texas — Though the StartupBus finalists for Monday’s judges' panel have already been decided, many of the companies that didn’t make the cut churned out interesting products.

Four teams from the Silicon Valley bus carrying "buspreneurs"...