The Euro has basically rised by about 50% against the GBP in the past 18 months.
Apart from financial markets, it looks like there are other arbitrage opportunities, which also confirm that on the short term at least, the GBP is undervalued against the EUR, as I show in the next paragraphs below. I am very bearish on the UK economy and have been for the past 3-4 years, but this shouldn't prevent you from taking such great arbitrage opportunities.
So, it's Christmas, and it's Sunday, so instead of going to my broker I might just go on the web and shop for Christmas presents. Here are some random thoughts:
Looks like you have to be selective anyway. This one is still cheaper in GBP but not by a massive amount:
[update] Disclaimer: Although I am short USD long EUR, I have no speculative GBP positions yet.
[update 20090304] Please read the follow up on this post here.