Boston's population varies with the seasons, but a more dramatic shift takes place nearly every day.
During standard working hours, the population of Suffolk County (encompassing Boston, Chelsea, Revere, and Winthrop) increases by 32%. So how many people is that, exactly? Over a quarter million — commuting in and out of the city on a daily basis.
This is cool: an visualization of Boston's bus routes and speeds, created by Bostonography. Oh, and it's real-time.