An old computer trick / prank / “fun” thing to do was piping random things to /dev/audio, or finding whatever program was available that could take any old file and not complain while translating it to audio by some means or another.

On my distro there are at least three of these programs installed by default: aplay, paplay and pw-play.

Some or all of these will complain if the file or stream they’re given isn’t a recognisable audio file, in which case, there’s a --raw or similar flag where it’ll just shrug and blast whatever through the sound system. If you’re creative, you can set different sample rates and hear it at different speeds.

VLC is just a really fancy way of doing the same thing.

For even more “fun”, try opening a file in Audacity / Tenacity, which will default to raw mode if it can’t tell what a file is, and you get to see the waveform and so on. Just take care not to modify and save over an important file with that.