Setting a different currency per product category

I would like to be able to set a different currency per category on my site (or per product), is that possibly?
I am setting up a site where I will have some products in GBP, some in USD and some in EUR.
I have set up your pro app on my site and for the items I want to display in EUR, I have given them all EUR prices, but I can’t find a way to get these items to display in EUR, I would like them to just show in EUR, as I don’t want them to be purchased in another currency.
I hope you can help me!
Thanks,
Will