Jackman's daughter Ava, 4, shows off her silly side in New York. Plus: Alicia & Jay-Z, Britney Spears, Halle Berry, Ashley Greene and more

2 of 16

DYNAMIC DUO

After giving a concert to commemorate World AIDS Day Tuesday night, Alicia Keys is joined on New York's Nokia Theatre stage by pal Jay-Z for a surprise encore of their hit, "Empire State of Mind." Proceeds from the singer's Amex-sponsored show – which streamed live on YouTube – benefited her Keep a Child Alive Foundation.