[geden]

A Fire Upon The Deep, shortly followed by A Deepness In The Sky (which is even more page turny but kinda requires AFUTD.

Across Real Time is also great and shorter.

[db48x]

I disagree with the notion that A Deepness in the Sky requires having read A Fire Upon the Deep. In fact, I would go so far as to say that each ends with an open question that is answered by the other, so that no matter which one you read first you will discover the answer in the second.