This is what background noise sounds like when you, first set your recording to automatically reduce noise, except to get this sound, put mic on sensitive, then increase the volume. Voila! computer noise!.
The keyboard sounds weird but i try the best to make it nature. The situation could be browsing facebook or website, which is you interested to click it and leave the message. Recording by miui hm 1w.
Another example on "listening" to a computer. Many sounds you hear are overtones from fans. The sharp noise is data transfers. Most of the sounds are caused by moving the mouse. The processors are not "heard" by placing a small antenna between the flat cables from two hard discs, you can capture the data packages. That may be done next time.
Konica minolta laser printer warming up and printing a single page, in raleigh, north carolina. Recorded head on to printer face on belkin sound recorder.
A recording of a computer connecting to the internet with a dial-up connection. I only edited it a little bit, just condensing it and removing background noise.