I've just come across a site that lists all supermarket and off-licence special offer prices -
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It seems free - I didn't have to register or anything - and it allows you to search on any combination colour/type/grape/supermarket/price. It seems a quick and easy way to find the best deals for Christmas vino!
Perhaps in the interests of truth and fair play I should say it's my wife's site, and I had a small hand in it's construction - so I didn't exactly "just come across it". However, that doesn't detract from the fact that it's free, has no pop-ups or banner ads, and will help UK dwellers seek out wine bargains. Visit it and find out for yourself!!
Pete Jones