For a more involved discussion of Frank Herbert and why he is one of my favorite science fiction writers, see Frank Herbert in Review.
"The Lazarus Effect" by Frank Herbert and Bill Ransom
The second (or by some accounts third) book in Herbert's "Destination: Void" series. This book finds Pandora's population divided between the Islanders, who live on organic floating islands, and the Mermen, a race of underwater dwellers who view themselves as racially superior to the Islanders. Following several generations after the events described in "The Jesus Incident," much of the action in this novel centers around one of the Mermen's political ambitions.
It's a good book, though not as good as "The Jesus Incident." Without the Ship character, this series struggles (literally) to find its center of gravity.
"The Ascension Factor" by Frank Herbert and Bill Ransom
The third (or by some accounts fourth) book in Herbert's "Destination: Void" series. This novel was completed after Herbert's death, and suffers from his absence. After his resuscitation from the hyb tanks that were orbiting Pandora, one of Ship's clones oppresses the masses. This book tries to be more political than previous books in the series, but fails in the attempt. It also has some serious plot holes.
"The Three Musketeers" by Alexandre Dumas
Athos, Porthos, and Aramis meet D'Artagnan for the first time, and the four adventurers/ladies' men become involved in intrigues between the French king, an English duke, and Cardinal Richelieu. This is an excellent book, and it's also quite funny. Far better than the morose "Man in the Iron Mask," although that was also a good read. I plan on reading "The Count of Monte Cristo" very soon.
"Man of Two Worlds" by Frank Herbert and Brian Herbert
The only book in which Frank Herbert and Brian Herbert collaborated. I would attempt to explain the plot, but it doesn't make a lot of sense anyway. A terrible book, and I am sorry I wasted so much time reading it.