A post from confirms what Zweisystem already knew, many streetcar/LRT systems operate twenty-four hours a day! Here we have an excellent example of the flexibility of modern LRT.
501 Queen and 506 Carlton. The routes are numbered 301 and 306 at night.
The Blue Night Network is the overnight public transit service operated by the Toronto Transit Commission (TTC) in Toronto, Ontario, Canada. The network consists of a basic grid of 22 bus and 2 streetcar routes, distributed so that almost all of the city is within 2 km of at least one route.