> Oops, not that it would matter much, but I thought it was Pathétique's 3rd
> movement's excerpt, "Allegro molto vivace". I'll listen for it
> again when I can to make sure.
No, I'm positive it was Pathethique's 2nd, Allegro con grazia, the 5/4 waltz theme played by the cellos. I've been listening to Tchaikovsky a lot lately, trust me.