These are in no particular order. Most of this is styling, I'm a very visual person. I don't race cars, so performance comparisons aren't as important to me as to some people, however I still feel that performance effects how attractive a car is.
I think my current favorite EU car is the current Mercedes SL styled cars. They are just effing perfect. And this goes from just a few years ago when I thought the only good Mercedes were old ones. They really hit a home run with the styling on the new ones.
The newest 3 series BMW is not bad, its better than the one just previous(E92 is better than E90), but the E46 3 series was another perfect looking car.
Ferrarri 599 GTB Fiorano: For some reason, to me the lines just work perfectly on this Ferrari more than any other. There's plenty of great looking Ferarris (the enzo is not one. The thing that makes it beautiful is that its ugly but purpose-built), but this one just comes together better to me.
Peugot 207. I like these for the same reason I like Mazda. Funky little cars that don't have to pack in a lot of horsepower to be really cool. The 207 is just a little more silly than the 206, which is also a nifty car.
Lotus Exige: once again, doesn't need to have a ton of HP to be cool. When you're looking for outrageous styling, Lotus has made it a way of life. Space aliens, man. But they're still good looking, especially because of nice proportions.