1. What's in your wallet? Well, as it turns out for more and more straphangers, advertisements. The Metropolitan Transit Authority recently rolled out ads for retailer The Gap on the front and back of select MetroCards—a revenue-raising move that is confusing some longtime straphangers. According to the New York Times, subway riders are having trouble swiping their MetroCards, which have sported the same gold and blue-letter design since 1997.
2. Fort Greene’s baby and toddler boutique is turning one year old today! Stop by the store for free cupcakes, balloons, party hats and flash sales all day long. My Brooklyn Baby, 692 Fulton St. 11 a.m. Free.
3. Looking to regain your "center" and help a community institution? Check out Brooklyn Free School's donation based Vinyasa-style yoga classes. Brooklyn Free School, 372 Clinton Ave. 7 p.m. Pay-what-you-wish.
4. Go: Organic Orchestra presents an unusual musical experience with their improvisational conducting and non-linear score. Roulette, 509 Atlantic Ave. 8 p.m. $10.
5. Alternate side parking rules are suspended for Columbus Day observances.