Hip-hop star PHARRELL WILLIAMS thrilled fans by making a surprise appearance onstage with Madonna in New York this weekend (begs11Oct08).

Williams joined the Holiday hitmaker during a gig at Madison Square Gardens on Saturday (11Oct08) to perform the star's hit Give It 2 Me, which he co-wrote and co-produced.

And Madonna used the show to continue her tirade against U.S. vice-presidential candidate Sarah Palin after slamming the Republican at two previous concerts on her Sticky + Sweet world tour.

She played a screeching note on her guitar and said: "This is the sound of Sarah Palin thinking."

And the Queen of Pop gave out condoms to the crowd with the politician's face on them, saying that she promoted safe sex - a dig at Palin, who has five children, including a teenage daughter who is expecting a baby with her boyfriend.

But the singer showed a more caring side to the crowd by dedicating You Must Love Me to her young daughter Lourdes, telling fans, "My beautiful Lola is 12 today but when I first sang this song she was growing inside me."