I feel like not many people know about this fantasy series by Megan Whelan Turner (see below). Maybe I am wrong; maybe it is not the secret gem I think it is, but, if not, if you're saying to yourself, "hey, dude, never heard of it", then check it out (both literally and figuratively!).
The first book, The Thief, won the newberry honor in 1997 and is a short novel with a clever twist (don't worry, I'm not spoilling anything; I knew there was a twist ahead of time and still couldn't figure it out!). Now, though I know people have heard of this first book, it's the second and third book in the series that I am not so sure people know about (but maybe I am wrong here). The second book,The Queen of Attolia, is where things really take off, in my opinion. The plot becomes much fuller, more complex, and more intense. Instead of one really great twist like in the first book there are several upon several untill your head starts to spin a little. The characters are ones you fall in love with, as is the way with any good book, especially the brash, rude, young thief who is the main character. The Third book The King of Attolia, has just recently come out and continues the storyline.
Maybe I just like the characters a little too much, but to me, these are lesser known, good books.