live train map of the London Underground

A Google and TfL hack that creates a live map of the trains pottering around the London Underground system in more-or-less real time.

Loving it.

Click here to check it out 

Update: looks like it was so popular, it broke!

TfL says "Owing to overwhelming demand by apps that use the service, the London Underground feed has had to be temporarily suspended. We hope to restore the service as soon as possible but this may take some days. We will keep everyone informed of progress towards a resolution."