I waited for twilight. Since the Casio QV10 has an automatic exposure system, if you want a long exposure, you need dim light. The exposure was the slowest the camera can do (I think) at about a fifteenth of a second. (There's no indication on the camera, so how do I know? - well, look at the reflections of the fluorescent light off the front of the train: there are seven and a bit. Since these lights pulse 100 times per second, that means the exposure included seven hundredths of a second!)
The other thing about this is that it's hand held. How do you avoid blurring at such a slow speed? Well, the QV10 head tilts, so you can use it like a twin-lens-reflex camera - point it forwards, but compose your picture by looking downwards. Thus the direction you are pressing the shutter release is the same as you are looking, which reduces blurring.
