Hi everybody. wow! this is a very interesting forum.
for any body wanting to see what a IBM 5100 portable computer looks like they can see one here:

you will have to type it in I guess direct links are not allowed. ((http://mercury.sfsu.edu/~hl/c.IBM.5100.html))
I am hoping this shows up ok and does not offend the moderators.
It is on the other board but I was not sure if the link to the other board was still on here.

Anyway it looks like a very interesting piece of machinery.
It will give you a better idea on the machine John is talking about that he went back to 1975 to get. how big it is and what it looks like.