Nokia is running a promotion in Poland where they are offering free taxi rides to Nokia Lumia owners within the city limits of Warsaw.
Their website notes:
Do you have a Nokia Lumia?
Order by Nokia Lumia one of two specially marked taxis.
Show the driver your Nokia Lumia smartphone .
Take advantage of free travel within the limits of the city of Warsaw
Trips have to be arranged via the app iTaxi.pl and the terms and conditions mean that one can only use the service every 96 hours, and other restrictions apply, but it is still a pretty cool promotion.
Read more at their website here.