8:05 a.m. Michael Bloomberg's weekly radio show hosted by John Gambling airs on 710 AM or at http://www.wor710.com
10:30 a.m. State Department of Environmental Conservation Commissioner Pete Grannis announces a crackdown on idling diesel trucks and buses. At the Othmar Ammann Playground, located at the northwest corner of 124th Street and First Avenue.
10:30 a.m. The board of the New York City Housing Development Corporation meets on the 10th floor of 110 William Street.
11 a.m. Military veterans gather in Times Square (Broadway between 48th and 49th) in support of Barack Obama.
Noon U.N. ambassadors from Africa speak at Columbia University's African Diplomatic Forum. In room 1501 in the Kellogg Center, 420 West 118th Street. (Until 5 p.m.)
2 p.m. "Scare Down the Greed on Wall Street" prayer vigil held at Federal Plaza, corner of Wall and Broad streets.
4:30 p.m. The Chinatown Tenants Union protests Michael Bloomberg's plans to develop the East River waterfront. On the corner of Catherine and Madison Streets.
7 p.m. The 35th Annual NY Village Halloween Parade begins at Sixth Avenue and Spring Street and processes north to 21st Street.
7 p.m. Council Member Larry Seabrook and community members hold an Obama-Biden get-out-the-vote event at Co-op City, 177 Dreiser Loop.
10:15 a.m. Suffolk County Executive Steve Levy keynotes the Stony Brook University staff convocation. In Ballroom A, Student Activities Center, SBU, Stonybrook.
11:30 a.m. Representative Steve Israel announces a new plan to help families care for aging relatives. At the Gurwin Jewish Nursing & Rehabilitation Center, 68 Hauppauge Road, Commack.