2008_12_modells.jpgMayor Bloomberg spent Saturday the same way many New Yorkers did—taking advantage of one of the final weekend days to get some shopping done before the holidays arrive. But unlike most, the mayor was playing not-so-secret Santa for two young Washington Heights siblings who had written their letter to St. Nick and addressed it to City Hall. They mayor picked up some sneakers, a basketball and a Hannah Montana gloves-and-hat set that were requested in the letter from 7-year-old Bryan Diaz, who said it was the first year his mother figured out the address to Santa. The mayor spent over a $135 on the pair in what's become a holiday tradition—not just for Bloomberg, but for guests of his holiday party at Gracie Mansion, who each year take one of the letters to Santa that wind up at City Hall. The mayor did his shopping yesterday at a Modell's in the Queens Center Mall, skipping the one near his home on the Upper East Side because as a spokesman said, "He is the mayor of all five boroughs."