I am currently listening to the audiobook of Raven Stratagem, which is the second book in Yoon Ha Lee's Machineries of Empire series. It's big military space opera with interesting politics, and technology which is really quite indistinguishable from orderly, spectacular magic. The silly part of this is that I listened to this audiobook for the first time in September! After I finished it the first time, I turned around and immediately listened to the first book, Ninefox Gambit, again (although I listened to it first in, I think, May) and then immediately plowed back into the sequel.
Besides being a really good recommendation of the books -- they made total sense the first time through, but I knew I'd find more little details and foreshadowings this way! -- it's not a very common thing for me. What books, if any, have you ever finished and then started again ridiculously soon?