This might be one of the most difficult TTT entries ever because there are so many beautiful covers out there... Please note that the fact that I like the cover does not automatically mean that I like(d) the book.
#1 The Name of the Wind - Patrick Rothfuss
I love covers that use black and another main color for contrast (which makes me a very easy prey for the editorial market). If this cover doesn't make you want to buy and devour this book, probably nothing else will. And believe me, this is one of those cases when you can judge a book by its cover.
More specifically, I like the second edition. The black background with a detail in one main color. These covers and the movie trailer for the first movie were the reasons that I decided to buy the books in the end, although a friend of mine had recommended them a couple of times before. If you made me pick only one cover, I'd go with Mockingjay.
#3 The Inspector Mascarell series - Jordi Sierra i Fabra
I like covers that use old pictures in black-and-white or sepia if they are tastefully used. Although they have little relation to the actual plot of the novels, I think they are nice. My favorite is the one for Cinc dies d'octubre (the third book), although the one for Dos dies de maig feels more appropriate for a detective novel.
#4 Matched - Ally Condie
This is a similar case to the The Hunger Games, only that in this case the background is white. The little green ball with the girl inside in the circle and the texture of the cover were the main reason why I bought the book. It catches your eye and I like the fact that's it's minimalistic and still attractive.
#5 Atonement - Ian McEwan
I'm kind of cheating here (as usual) because this is part of a collection that Vintage Books edited on their 21st anniversary. I'm putting Atonement in the list because it's the one I have, but actually it's the whole collection that I like (special mention to Haruki Murakami's The Wind-up Bird Chronicle). The picture is not especially good, but I like the monochromatic scheme of the covers.
#6 Blind Willow, Sleeping Woman - Haruki Murakami
I have the Catalan version, but I prefer the English one by Vintage Books because it's minimalistic and it has a clear Oriental design that I find appropriate to the book.
#7 Die Frau des Zeitreisenden - Audrey Niffenegger
This time, the German edition by Fischer Taschenbücher. It is a pocket edition that actually fits in your pocket and has a very thin paper, so it's perfect to carry around. If you don't like it, you can rip off the round red sticker with the title and name of the author so that the cover looks more like a personal diary. The pattern reminds me slightly of kimono fabric.
#8 Run - Ann Patchett
another cover. I think the one that I have is the British one, which is the one that I'm posting here, although I'm not quite sure. I prefer this one because it looks calmer and bares more relation to the plot than the other one.
#9 Eighty Days Yellow - Vina Jackson
I know, I know, I said that I wasn't a big fan of this novel nor this genre (although I honestly thought it would be worse). While the cover goes along the lines of every other cover of every other recent erotic novel, at least this one is done tastefully (in my opinion, of course) and kind of says without words what you will find inside.
#10 A Thousand Splendid Suns - Khaled Hosseini
If you haven't noticed the pattern by now, I like minimalist covers with a main dominant color. The cover is only one of the many things that I liked about this book. If you still haven't, go read it now.
Here is a selection of covers that I thought of and almost made it into the list for many different reasons, although you can see the pattern (minimalistic covers, one dominant color) still kind of applies. The are many more covers that I'm sure I didn't think of. Feel free to share your opinion in the comments section!