be629673_ovember___Oldskooler_Ramblings__The_Good
[Feature] Used “sidecars” instead of slots [The Bad] Locked you into IBM proprietary expansions [The Ugly] You could quite literally double the width of the machine with a crapload of sidecars attached to it [The Good] 
Very easy to expand the machine without opening it
2008 November « Oldskooler Ramblings
The Good