Help needed: FOSS for public transportation systems

Do you know of free and open source software (FOSS) for managing public transit (public transportation) systems? Especially small, bus-based systems. Perhaps I don't know the lingo well enough, but all I can find are expensive, proprietary systems. You would think there was a need.

As in earlier requests, pointers to good association or government sites, or thoughtful blogs, are also welcome.

Helping Lower Walnut: a free antivirus

You'll recall the Rev. Angela Mather and her cash-strapped parish in Lower Walnut, Maine: a use case for free and open source software and other solutions for congregations.

One of the problems she had was an old Windows computer that was sluggish and temperamental. A friend from seminary thought it might be infected with viruses.

But anti-virus programs cost money or lead you on with a limited version. But there is a free (intellectually and financially) version called ClamWin that she can use. There's also a portable version you can keep on a USB drive in case you have to use a strange computer.