Here's the article about it I remember reading at the time...
That was fun. Perhaps we should do it again!
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The date said 15th Oct 2008 but that could be a red herring. My gut feeling is a private showcase that at the time we didn't hear much about but I suppose it could have been a tv appearance with a snazzy outfit like that.
Answers on postcard... o actually, since Royal Mail are striking left right and centre, (but the BBC is BIZARRELY NOT TELLING ANYONE ABOUT IT - I sent a first class large letter to London Sept 26th and they got it yesterday!) you'd better leave a comment instead.