Nice going John!
We have an AFOL! Adult Fan of Lego! 
I expect to see pictures of course. 
Eric
The main layout was never 'finished' so no overall pictures exist.
Some of the trains in their parking area.
Track maintenance gang on their vehicle. (These guys are actually cheap immigrant labour from across the border in the Playmobile world).
Vehicle is built on a single 12V power bogie fitted with DCC decoder chip and wire brushes to operate on the 9V track.
Steam locos require a lot of TLC.
Very rare 4-4-4! It is an MOC with 9 with articulated chassis on the loco and a 9V bogie with DCC decoder under the tender.
Testing the geometry for a spiral, it is only really reliable for the downward direction or for a single loco going up. The track maintenance guys take this a full throttle, up and down.
We have 4.5volt battery trains, quite a few 12v trains designed to run with a double central conductor rail and a number of 9V trains that run on metal conductive rails.
The 4.5V trains have been converted to rechargable cells in the battery wagon with pickups underneath to contact sections of 12V conductor rails. If the conductor rails are live a simple circuit in the train stops the train and the battery begins charging, when power is cut to the section of rail the train takes off under battery power. Some quite complicated sequences can be arranged using these trains and timer circuits to drive the sections of charging rail. Sequences include a loop with a passing bay and contra rotating trains, the passenger train stops at the platform and the freight train stops inside a freight shed.
The 12V trains have been fitted with wire brushes to pickup from the 9V track and the standard 9V trains of course run on the same track.
The track voltage is about 14Volts frequency width modulated AC and the DCC (Digital Command and Control) decoder chips extract control commands from this, rectify for DC and feed pulse width modulated DC to the motor according to the settings at the remote control unit.
DCC also does things like control lighting on the trains and switches track points etc.
