A modular system can be pretty simple and yet loooots of fun... a friend of mine has 8(or 6?) rackspaces of Doepfer and AnalogSolutions modules (4 vco's in all)... still worth quite a hefty load of cash but damn that thing is a blast!!! You never get tired of it. Well invested money I think... depending on what you do, of course... he also has a Monopoly, that bastard.
those are just nuts you would never learn how to use it fully.
maybe that is why the in the first pic the the guy is old looking, the machine did it to him.