Symphonic flash mobs

I think they're amongst the most impressive of flash mobs. Do you have any idea how hard it is to lug around a harp or a double bass? Let alone timpani. Yet here the performers appear out of no where with their heavy instruments, enchant their audience and disappear into the crowd.

This one is my personal favourite: the Copenhagen Philharmonic perform as a flash mob in Copenhagen Central Station.




And here, a performance of Symphony No.9 (Beethoven)





A little closer to home: the New Zealand Symphony Orchestra perform with guitarist Justin Firefly Clarke.