[Jack_]

...as well as some other things for C4's 30th Birthday in January.

Comic Jimmy Carr is to host nerds' favourite Countdown as part of a TV job swap that will see several of Channel 4's big names doing other shows.

Jimmy will take over Jeff Stelling's role as presenter with his 8 Out Of 10 Cats sidekicks Sean Lock and Jon Richardson grappling with the words and numbers as contestants.

Meanwhile Alan Carr will bump Phil Spencer out of the frame and join Kirstie Allsopp for a special edition of property search show Location, Location, Location.

Camp Alan will even get to do some hard bargaining as he tries to bag a new pad for a single woman.

Phil won't be left empty handed though — he will be replacing Davina McCall as the host of Million Pound Drop — with Davina PLAYING the general knowledge quiz.

And The Made In Chelsea mob will be cooking each other a feast on a Come Dine With Me Special.

The shows will all air over one night next January to commemorate the channel's 30th anniversary in 2012.

Throughout the night — dubbed the Channel 4 Mash-Up — rolling hosts will introduce each show plus sketches and some very special guests.

A source said: "We've kicked around a load of ideas about what to do to mark the 30th anniversary and this is one that will use all our best-known faces in a quirky way.

"The emphasis will be on comedy but there will be some serious moments — like when Alan has to get tough to sort out a house price deal.

"Sean and Jon are both good wordsmiths so they will no doubt be getting quite competitive on Countdown."

Sounds good! Hope Noel gets to play Deal or No Deal