The laptop was built in probably 1990, which is ancient history for most any computer. Amazing it still even works. It was a sort of a nettop before anyone ever though about nettops. As you can or will see the floppy and the dvd-rom drive were external so that you did not have to use them unless you needed to. Hard frive is removeable also.
Note: you could do this just one machine or a whole office or school.
Step 1: Doing fine
Step 2: There goes the DVD-rom drive
Step 3: HD is dead.
Step 4: Is that a cable?
Impossible you say?
What was done was not a trick, so how was it done? See: http://www.instructables.com/id/Another-almost-free-computers-thin-client-set-up/