Well then there are always those pieces that composers have transposed either from orchestra to piano or orchestrated from the piano they wrote it for. Famous example is Ravel's Pavane for a Dead Princess, originally composed for piano. Ravel rewrote it for the orchestra, which is the more commonly-known version, but the piano version is still decently commonly-heard. That's the first one that came to mind for me.

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"Aufersteh'n, ja aufersteh'n
wirst du, mein Herz, in einem Nu!
Was du geschlagen
zu Gott wird es dich tragen!"
-Gustav Mahler