You can see subway too. Both Toei and Metro operated lines. Their colours are faded to indicate underground.
I was impressed to find the JR train I am currently sitting on. As my train started moving out of the station, its simulation moved immediately. I cannot tell whether this is realtime data or just because the train is perfectly on schedule.
I haven't found one for London (my hometown), but there is this interesting animation project that uses historical data to demonstrate passenger flow on the system. http://wgallia.com/#!underground
Similarly, Paris is building 200km+ of new fully automated, fully grade separated, mostly underground metro covering the Paris metro area, and using the opportunity for urban redevelopment as well:
Very cool, but FYI, this is not a "subway" map. It is a transportation map. Trains, Planes, Monorails. The page's title is "Mini Tokyo 3D" not "Real-Time Tokyo Subway Map"
From 2008 to 2012 a friend and I spent at least 2 - 3 times per week obsessively 'running track' in the Paris metro.
It's definitely one of the most interesting systems in the world, with a lot of hidden secrets. Despite years of systematic exploration, and having walked the length of the entire system, we were still finding artefacts.
For the interested, in my opinion the most complete writeups of the system was written by my exploring partner.
In Paris, we used to have special boards at big stations: a map of the subway system, and a button board with one button per station in the city; if you pressed a button, the path would light on the map explaining how to reach it:
I've had this project in the back of my mind for a long time. Use some kind of discreet inertial navigation while riding subways, then render the paths over views looking down from above-ground. Kind of like an over (under) lay to see where the trains actually go. You can hear the subways rumble in many shops along the lines, but I'm always curious where exactly they are -- imagining the ground was transparent and I could just see those people sitting while zipping by underfoot.
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