I beg to differ.  WD40 works on a lot of stuff, but it
usually works
 better as a solvent than as a lubricant. 
Or a...I'm not sure what the word is.  A liquid with which one washes
gunk out/off of something.
A bike-shop guy once told me to never use WD40 as a lubricant for
things bicycle, but that it works fine to wash dirt off (say) a chain,
preparatory to lubricating it.  (As lube, he recommended automatic
transmission fluid - apparently it's made with a good grade of oil
under very strict quality controls, and is widely/cheaply available.)
Now, bicycles aren't computers, but it does seem to me that similar
remarks should apply to anything with complicated mechanical parts,
such as an ASR33 or a Selectric...though you might want to use grease
rather than oil as the lube once you've washed it relatively clean.
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