[Harmless Teddy Bear]

as he is one of those very rare classical composers—like Mozart or Beethoven, but who else? –whose music almost everyone has heard at least a few bars of, even if they can’t always identify it.

Edvard Grieg. Almost everyone knows "Morning Mood" and "In the Halls of the Mountain King".

Rachmaninoff, "Flight of the Bumblebee" Shostakovich, "Second Waltz"

It is not really rare at all.

[left that other site]

Flight of the Bumblebee was by Rimsky-Korsakov.

Rachmaninov’s 2nd Piano Concerto was used for the Soundtrack for the Marilyn Monroe Movie “The Seven Year Itch”, and also had at least two Pop songs derived from it. “Full Moon and Empty Arms” and “All By Myself”.

But you’re right about Grieg. :-)