Hey GamingOnItch, thank you so very much for playing and your comment. The following is on the left panel. The computer you are referring to is a tape deck. Just press play, and turn your volume on and enjoy. ;)
Other notable features of the left pane are...
PORTIA's Piano — a real, playable two-octave keyboard (mouse or your physical keyboard). Has secrets baked in: play "Twinkle Twinkle" and you unlock a hidden achievement plus a star shower; play the four notes from "the Signal" and you unlock another one tied to a piece of lore.
The Harmonograph — a mechanical drawing toy, pendulum motion traces out geometric patterns on screen, the classic physics-desk-toy look.
The Double Pendulum — a chaotic-motion physics toy, the two-armed pendulum that never repeats the same path twice.
The Prime Spiral — a visual built around prime numbers spiraling outward (an Ulam spiral), matches the game's whole "PORTIA loves math" thread that also shows up in her journal entries.
There are many secrets, bobbles, widgets and hidden easter eggs buried in the game, poke around... tell me what you find.