This Keyboard IBM Manufactured by LexMark (1984) still works :P and I love the large wire it has.
However, it is heavy and makes a lot of noise when typing.
I do use this for repairing some computers and currently using it with my Pentium 4 machine running Windows 7. I know it is weird, a strange keyboard combination with a small laptop mouse. xD
And also some key letters dissapeared, it has double cap, one is like old typing machines and the letter as a cap covering the key.
I'm currently missing these letters:
ESC F4 F9 F10 PrtScr Pause 1 2 ' + } .
. and - at numeric pad
and the right Ctrl key was ripped off fully, only left the spring, which is very well attached.
Summary: Good old things lasts better than newer devices.