Provided that you have one, of course.
This was always mine. The apropriately named Waltz of the Geese - the Blue Danube..

Where did you first hear your favourite?

Edit: I hate autocorrect sometimes.

Scriabin – Sonate No. 5, Sonate No. 8
Satie – Socrate, Gymnopédie No. 2

I searched for them on YouTube. Scriabin I explored after hearing about him, and I fell in love. I read a biography of Satie that named Socrate his masterpiece. I listened; I agreed.

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I recognize the first. Don't think I've heard the others.

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Satie's Gymnopédie No. 1 you may well have heard. It's very famous. No. 2 is less so, though still well-known.

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Nice picks.