IT promises the ultimate in celebrity fashion bargains. Not sweatshop rip-offs, but the real thing. A glitzy charity shop crammed with stars' cast-offs, including Carey Mulligan's Bafta gown, has been launched by Zoe Ball, Beverley Knight and Annie Lennox.

The temporary second-hand store, billed as "Britain's biggest charity pop-up shop", includes one-offs donated by Beyonce, Alexa Chung, Elle Macpherson, Dame Helen Mirren, Little Boots, Dame Shirley Bassey, Dame Vivienne Westwood, Anya Hindmarch, Stella McCartney and Christian Lacroix.

The Oxfam Curiosity Shop will take up residence in Selfridges' flagship Oxford Street store in London from Algeria today until next Thursday. Various celebrities will put in appearances at the shop throughout the week.

Several A-list items will also be auctioned online, offering fashionistas from around the world the chance to bid for the pieces.

Cash raised from the project will help Oxfam women's projects around the world.

The auction includes Mulligan's chic floor-length size 10 Vionnet dress, which she wore when picking up her Best Actress Bafta for her role in An Education.

The floral gown is up for grabs at curiosityshop, and bidding started at just pound(s)50.

Mulligan said in a statement: "I'm honoured to be able to donate my Bafta dress to support Oxfam's work helping women living in extreme poverty across the world."

Ball, who browsed the top-of-the-range items along with Knight and Lennox, donated items including a pair of Louboutin shoes that she wore to last year's Sony Radio watches-c Academy Awards.

Other items donated include an original, one-shoulder butterfly tunic dress by Beyonce's US fashion label, House of Dereon, and a pair of Elle Macpherson's thigh-high Dior boots.

Lennox helped Knight try on a pair of yellow snake-print boots and donated a shimmering gold dress to the shop. She said: "Ever since I was a kid, I've always loved second-hand clothes."

The shop will also stock more than 6,000 hand-picked vintage and high-end items, including clothing, accessories, music, books, homewares and art, donated to Oxfam branches from across the country.

Sarah Farquhar, head of retail for Oxfam, said: "To see such a powerful group of women come together and plough so much time and energy into a project has been incredibly inspiring.

"The shop is a very exciting venture and we can't wait to see hordes of keen Oxfam shoppers being wowed by the truly amazing stock we have waiting for them."