First, thanks to Laura Segel, I heard about The Back Bay Midnight Pedalers which will hold its 19th Boston by Bike at Night on August 18th.
The ride starts at midnight downtown, watches the sun rise and ends at Christopher Columbus Waterfront Park. The tour hits the city's many historic sites when the hour and darkness offer riders freedom on otherwise crowded and narrow city streets. (More details.)
Second, Hub on Wheels is running its citywide ride and bike festival in Boston on Sunday Sept 23 (more details).
I am unlikely to do the midnight ride (like Cinderella's carriage, my bike turns into a cucumber at midnight), but really hope to do Hub on Wheels event. Let me know if you want to join me.