Britney Spears is set to auction off the outfits she wore from How I Met Your Mother, with proceeds going to an environmental charity.

The pop wreck appeared on the hit CBS show last night playing a receptionist named Abby who becomes obsessed with the show’s main character Ted.

Her appearance on the show went down well, with the usually troubled Britney raising laughs and, some say, making a return to form.

The clothes that she wore on the programme are due to be auctioned off via SeenOn, with one dress already fetching $900.

All the money raised from the auction will be donated to Natural Resource Development Committee, a charity that helps with environmental issues. Al Gore would be proud.

To see photos of Britney in action on How I Met Your Mother click here.