Instead of a performance by the characters of “Foster’s Home for Imaginary Friends,” onlookers were treated to a rendition of “Never Gonna Give You Up” by singer Rick Astley.
The switch happened on Thursday morning, during the annual Macy’s Thanksgiving Day Parade. The puppets on the float featuring the Cartoon Network show began to sing 1970s hit and TV theme song “Best Friend,” but stopped abruptly, revealing Astley, himself, dancing and singing to his signature tune.
http://www.hollywoodtoday.net/2008/11/28/rick-astley-rickrolls-macy%E2%80%99s-thanksgiving-day-parade/ to story. Link to video. -Thanks, Billy Ting!