Thanks to the Brooklyn Paper for letting me borrow their lovely list of weekend subway changes:
F: Manhattan-bound trains skip Fort Hamilton Parkway, 15th Street-Prospect Park, and Smith-Ninth Street stations (all times until May).
G: Trains run in two sections: Between Court Square and Bedford-Nostrand avenues, and between Bedford-Nostrand avenues and Hoyt-Schermerhorn streets (Friday, Feb. 11 at 11 pm to Saturday, Feb. 12 at 6 am). No trains between Church Avenue and Bergen Street. Queens-bound trains skip Fort Hamilton Parkway and 15th Street-Prospect Park stations (all times until May).
A, C: Manhattan-bound trains run on the F from Jay Street-Metrotech, skipping High Street.
D: Trains run on the N line between Stillwell Avenue and 36th Street (Saturday, Feb. 12 at 4 am to Sunday, Feb. 13 at 10 pm). Manhattan-bound trains run express from 36th Street to Pacific Street, then skip Dekalb Avenue.
N: Trains run over the Manhattan Bridge between Dekalb Avenue and Canal Street (Saturday, Feb. 12 and Sunday, Feb. 13 at 12:01 am to 6:30 am, and Monday, Feb. 14 from 12:01 am to 5 am).
Q: Manhattan-bound trains run on the R from Dekalb Avenue. Manhattan-bound trains skip Avenue M and Avenue H (all times).
R: Trains run over the Manhattan Bridge between Dekalb Avenue and Canal Street (Saturday, Feb. 12 and Sunday, Feb. 13 at 6:30 am to midnight). No trains at Court Street and Jay Street-MetroTech. Manhattan-bound trains run express from 36th Street to Pacific Street, then skip Dekalb Avenue.