What is Pilluralli?

Way to use free-time at weekends in Finland. It is mean literal "Pussy-Rally".
Pilluralli mean pointless car driving along streets of town with friends and chatting with them at parking lot. Drivers are often male, aged 18-25, most cases vocational school graduates (Amis)
During pilluralli drivers listen often techno or else hitmusic loud.
Pilluralli appears mostly smaller towns.