The original Sinclair ZX Spectrum manual featured a listing to play a few bars of Mahler's First, with the reader asked to play the whole piece as an exercise. Here's Matt Westcott completing that exercise with the help of a few friends and a table covered in Spectrums. In the process of making this possible it is also believed that the record was broken for the number of networked Spectrums in one place.

Actual title:

    Mahler's first symphony, as played
    by 12 networked Sinclair ZX Spectrums

The first 7 minutes are explanations of the challenge and how it came to be. Actual "performance" starts at the 7 minute mark.