This online auction, which aims to make money for Sport Relief, gives the public the opportunity through microblogging site Twitter to buy prizes from their favourite stars.
There are currently more than 100 celebrities taking part, including Stephen Fry, Sara Cox, Olly Murs, David Walliams, Gabby Logan, JLS and Sarah Brown.
Fashion designer Matthew Williamson has offered an exclusive designer dress to his highest bidder, rugby player Chris Ashton pledged that he will give his winning bidder a signed England rugby shirt and boots, and male model David Gandy is auctioning himself off for a lunch date.
From today until Sunday, March 25, the Twitrelief stars will be regularly tweeting about the auction and their prizes.
Gabby Logan said: "It's great that Twitrelief is back again this year. I'd like my prize to be the one that everyone bids for, so I'll be encouraging everyone out there to bid as much as they can and they'll be rewarded with lunch with myself and the lovely Clare Balding."
Actor Nick Frost wrote: "There will be no escaping me as I follow this person on Twitter, and to increase my bids I'm offering a once in a life time opportunity to have a walk on part in my next film... maybe it will be the highest bidder's lucky break!"
David Gandy said: "For this year's Twitrelief I'm offering the highest bidder the chance to have lunch at one of London's top restaurants for some great food and plenty of wine, the only downside is, they have to have lunch with me."
Last year, celebrities such as Piers Morgan, Leona Lewis and Alan Carr auctioned themselves off for the cause.
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