I found this last night, and this evening myself and a colleague kind of looked up bus routes on londonbusroutes.net and... errrrm... drove them to timetable
It's powered by Google Maps so it does need a fairly reliable internet connection to run smoothly (and the processor speed also seems to make a difference), and some areas may not have very good mapping available. You can either select a place in the drop-down menu, or type a location into the search box. Choice of vehicles is in the box on the top-left. Arrow keys control the vehicles. Don't forget to indicate
To make the speedo read in mph then click it. Clicking it toggles between km/h and mph. The small red 'Reset' button sets the odometer to 0.
http://geoquake.jp/en/webgame/DrivingSimulatorGM/
http://geoquake.jp/en/webgame/DrivingSimulatorGM/