Retiral revived interest in my model railway. 50+ locos & already sectioned track meant DCC was not attractive. I use DC with Pulse Width Modulation (PWM) controls (using Arduino) & a wireless controller to allow "roaming" without a trailing cable. I have radio controlled locomotives; great for those with poor power pickups & allows independent operation on track with conventional locos. In some track powered locos, I have Arduinos and MP3 sound along with directional lighting. My coaches & brake vans have lighting which take power from the track but remain on for a period after power down via "super capacitors". Points & signals operate automatically (Arduino). In addition to some buildings, I have updated some old Triang stock (Giraffe Car, Livestock Wagon, Caboose) to receive infra-red controller commands to make sounds, shows lights, move characters & open/close doors. Way back, I used to take photos of 1:1 railways, some are on YouTube. I've also an interest in MIDI music systems.