The Saint Petersburg and Moscow State Orchestras, two of the best in the world.

You're all forgetting the most significant gift they gave us: Russian dressing.

And no one's mentioned food...

Chicken Kiev
Beef Stroganoff
Blinies
Caviar

and lots of other foodstuffs I've never heard of, listed here

Jayne

And, of course, that zany Russian parlor game, Russian Roulette.

Music!

A few of my favourites:

Stravinsky, The Rite of Spring, The Firebird
Mussorgsky, Pictures at an Exhibition, Night on the Bare Mountain
Rimsky-Korsakov, Scheherazade
Borodin, Polovtsian Dances
Rachmaninov, Rhapsody on a Theme of Paganini
Prokofiev, Romeo and Juliet, Peter and the Wolf

:-)

Mandelstam, Akhmatova, Brodsky.
Solzhenitsyn.
Pasternak.

Tsvetaeva

Nemo

kalashnikov ak47

Yes, that is certainly Russian, and it's been provided to the world.