Tony Blair and Kate Moss joined a host of stars to perform in the Comic Relief TV show to raise funds for good causes.
Peter Kay and Matt Lucas duetted with The Proclaimers
By the end of the show, it was announced that a record-breaking total of £40.2m had been raised.
Peter Kay and Matt Lucas duetted with The Proclaimers on the classic single I'm Gonna Be (500 Miles) with the song instantly available to buy online.
Prime Minister Tony Blair appeared in a sketch with comic Catherine Tate's teenage schoolgirl character Lauren.
He used her catchphrase "Am I bovvered?" repeatedly to Lauren's dismay.
"Meeting Lauren was an experience in itself, she didn't seem 'bovvered' by anything," Mr Blair joked.
"But I hope she will put her time spent at Number 10 to good use."
Girls Aloud and the Sugababes kicked off the BBC One show at 1900 GMT by performing the Red Nose Day single, Walk This Way.
The show's celebrity cast-list has already included James Bond star Daniel Craig, supermodel Elle McPherson and Little Britain stars Matt Lucas and David Walliams.
Socialite Tara Palmer-Tomkinson won the final of Comic Relief Does Fame Academy, which raised £780,000 through viewers' votes.
And former Daily Mirror editor Piers Morgan heard the words "you're fired" another time, as he was sacked by Sir Alan Sugar from the celebrity version of the Apprentice, Comic Relief Does the Apprentice.
Ant McPartlin and Declan Donnelly visited Africa
The fundraising marathon has also featured the last ever episode of The Vicar of Dibley, which saw pop star Sting move in with Dawn French's character, Reverend Geraldine Kennedy.
Jonathan Ross, Russell Brand, Paul O'Grady and Davina McCall are among the presenters during the eight-hour marathon.
Indie rockers, The Killers, took to the stage with pop stars Take That also performing.
Sketches came from the likes of Borat star Sacha Baron Cohen, Little Britain, The Mighty Boosh and David Tennant.
Proceeds from Comic Relief: The Big One go to charities in the UK and Africa.
The appeal was launched on 31 January but the majority of money will be collected on Friday - known as Red Nose Day.
Friday marks the 11th Red Nose Day and the 21st year of Comic Relief.
The charity has raised more than £425m in that time.