What are your favorite Star Trek books?

I just finished "A Stitch in Time" and started looking for some other Trek books.

Ended up buying the Millennium trilogy and the Destiny Trilogy.

Was going to start reading Millennium, but when I read the preview/prologue for Destiny before I bought it, it started out with Sisko and Jadzia discovering the derelict remains of the NX-02 Columbia in the Gamma Quadrant, and I was hooked and had to buy/continue reading that one.

Which ones have you read? Any other recommendations?

Oh, also, I'm gonna slightly plug ebooks [dot] com since they have a huge selection of DRM-free books, and all of the Trek books I was looking at were available without DRM. Saves me the hassle of jailbreaking an Amazon purchase or buying it from Amazon and pirating a DRM-free version I can actually use.