It can also be said that Fame Academy was a copy of the Pop Idol programme - but I don't want to say that as we have covered all this ground many a times and all channels 'copy' each other idea's and adapt certain ideas into new ideas.
It could even be said that Eastenders was a copy of Coronation Street - but I don't think we'll explore that one - it's endless. Everyone copies/feeds off existing programmes.......
Vice-versa (BBC copying from ITV) I can think of a few of the more blatant carbon-copies, off the top of my head...
BBC1's Real Story = ITV's Tonight with Trev (a total rip-off, right down to the music, the style of graphics and the studio-based presenter at the beginning/end)
BBC1's Good Morning With Anne & Nick = ITV's This Morning
BBC1's Rogue Traders = ITV's House of Horrors
Also I vaguely recall ITV doing a one-off interactive "Test Your IQ" type show, hosted by Gaby Logan and some bland identikit male presenter (Mark Durden-Smith?) - it was an exact replica of BBC1's Test The Nation, but I can't remember which came first.
Saturday Showndowns' 'Supermarket Sneak' = stolen from pre-filmed material for Dick and Dom (game title unknown)
Technically the entire Saturday Showdown could be seen as a copy of Dick and Dom in Da Bungalow. Kids invited into the place to take part in games to get points. Just change the presenters and then alter the set from being a bungalow to a basement flat.
If I recall it was later explained that it was called 'Magpie' because Magpies tended to steal things, and that was what they were doing (ie. stealing the format from Blue Peter).
News At Ten (1967) - Nine O'Clock News (1970)
TV-am (idea proposed 1980) - Breakfast Time (planned later, launched earlier)
Childrens ITV strand/IVC (1983) - Childrens BBC strand/IVC (1985)
Neighbours (regular Teatime programme that got alot of young viewers, 1986) - Home And Away (same thing, though about 1988 or 1989)