Which are your favourite opening sequences for films ?!

Which are your favourite opening sequences for films ?

Any why ?
Many 007 films open with spectacular set pieces, but others are good too.

e.g. The Shining - fabulous helicopter shots of mountainous scenery with music of similar size.
Apocalypse Now - helicopters again, criss-crossing in front of the jungle, which then explodes to the sounds of The Doors - The End.

2001