1 of 7 Sir Ian McKellen (right, standing) has starred in some of the most successful films in history and had two Oscar nominations - but one of his lifelong ambitions was to join the growing number of celebrities who have taken minor roles in TV soaps.
2 of 7 The Prince of Wales popped into the Rovers Return to mark Coronation Street's 40th birthday in December 2000. Viewers saw characters watch a news report about the prince visiting Weatherfield.
3 of 7 Sir Cliff Richard (centre) was seen as an extra having a drink in a 1997 episode with Andy McDonald (Nicholas Cochrane) and Liz McDonald (Beverly Callard).
4 of 7 Little Britain's David Walliams (left) was drafted into EastEnders to play a fake registrar at the wedding of Alfie Moon (Shane Richie) and Kat Slater (Jessie Wallace).
5 of 7 Comedian Peter Kay appeared in Coronation Street to take Shelley Unwin (Sally Lindsay) on a date. The Phoenix Nights star, who co-wrote his role, also played a shop fitter in 1997 before finding fame.
6 of 7 Veteran funnyman Sir Norman Wisdom turned up in Corrie last year, playing elderly fitness fanatic Ernie Crab.
7 of 7 Former Blue Peter host Peter Purves had a cameo role in EastEnders in 1987 to interview the Albert Square residents for a fictional TV documentary. The characters were horrified by the way he misrepresented them.