I normally don't watch the Macy's Thanksgiving Day Parade, but in 2008 I just happened to be in front a TV when the Cartoon Network's float come down the street and boom! There was Rick Astley signing. It was awesome!
For those who don't know what a RickRoll is, here's a look from Wikipedia:
Rickrolling is an Internet meme[1][2] involving the music video for the 1987 Rick Astley song "Never Gonna Give You Up". The meme is a bait and switch; a person provides a hyperlink seemingly relevant to the topic at hand, but actually leads to Astley's video. The link can be masked or obfuscated in some manner so that the user cannot determine the true destination of the link without clicking. People led to the music video are said to have been rickrolled. Rickrolling has extended beyond web links to playing the video or song disruptively in other situations, including public places, like an appearance of Astley himself in the 2008 Macy's Thanksgiving Day Parade in New York. The meme has helped to revive Astley's career.