OpenTTD is game about trains and transporting.
Upstream/official homepage: http://www.openttd.org/
Port homepage: http://openttd.projects.openmoko.org/
It contains now open graphics and open sounds. No proprietary data-files needed.
Install from opkg.org:
Look project page how to compile for Freerunner.
You can move screen with stylus, just point empty place and drag. If this doesn't work, check: Advanced settings -> Interface -> Interaction ->Left-click scrolling: On
OpenTTD is railroad and transporting game.