Google Maps for Mobile, an application that can make your travelling a little less stressful, and Google Maps for Mobile apparently allows the user to tell the world how fast they are going, and where they are on their mobile phone.
That is of course if you enable My Location in Goggle Maps for Mobile, and when you do so, your Google Maps with My Location mobile phone sends off anonymous bit of data to Google letting them know how fast you are moving.
Doing this enables Google to combine thousands of mobile phones moving across an area and then can gain a good picture of traffic conditions and return the info in the Google Maps traffic layers; for more hit up the link.