Not that i wanted to dig up an old post, but i was really wondering about this myself when i found this thread allready existed.
So my 2 cents are: (i am for some comics translating the titels into english myself since i dont know if they have been released in the usa at all)
Rogon the red wolf
Murena (really loved this one, about the roman empire)
Eagles of rome
Douwe Dabbert (can't really translate, because its a name)
Druuna ( XXX comic, but with incredible art)
What i love about european comics is that they seem far more mature sometimes. Sex is a lot more featured. Don't be surprised if you suddenly find yourself reading about some sexual act in what is normally not seen as a XXX comic.
For instance Murena is such a comic. Also i just love the hyperrealistic art by Don Lawrence in Storm or Trigië, or in the Mercenary by Segrelles.
Even though Druuna is a very hardcore porn comic, the art by Serpieri is very realistic and amazing but should not be read by non adults. ( i would love to see him do a Wonder Woman comic, without the porn of course)
Its like Alex Ross is drawing every comic from beginning to end instead of just covers.
I love the format as well, normally they cost a lot more, but most of the time you get a somewhat finished story in one book, so you don't have to wait a couple of months before you have the whole story together like in usa comics.
On the other hand, european comics are released a lot less frequent than american comics. Sometimes they are years apart.
Well let i just finish by saying you are really missing out on some great stuff if you don't read european comics. Of course the language barrier can be a great hindrance to people. But if you can get your hands on some translated copies do not hesitate.
(and i know that some fans do their own translations, but now i am wandering into a grey area thats not entirely legal)