Re: TOS: The Joy Machine by James Gunn (Spoilers!)
I first read this novel back in 2002/3 as part of a
TOS book marathon I was doing. I didn't really remember much about it, apart from vague flashes of Kirk receiving his "payday", something involving whales and an evil computer.
I know that some readers aren't huge fans of the
five-year mission stories, and I can certainly understand the reasoning behind it. For me though, they provide a break from the ongoing 24th century narrative where you've got to be on the ball remembering who's assigned to what ship or station and what happened to the
Enterprise crew in a Deep Space Nine novel and that sort of thing.

Not that I'm complaining, I adore those books. It's just nice to immerse yourself in a simple
TOS novel.
The Joy Machine is probably as
TOS as it's possible to get as the storyline and the various themes around it were explored in several (and better) episodes such as "The Return of the Archons", "A Taste of Armageddon" and "The Ultimate Computer" which saw Kirk and co come up against computers which think they know the best for humanity and have to be set right. With that traditional, well-trodden ground, it's never really going to excel.
To me the most interesting part of the story was when Kirk was captured and taken the Timshel's polar region to live with the scientists, turned rebels, for a few weeks. It was during Kirk's stay that we learned that the scientists had learned how to communicate with wampuses, a whale-like creature native to Timshel. These wampuses then assist the fleeing scientists escaping an advancing wall of ice. This would be a far more fascinating story to explore, but it's quickly passed over as we get back to tackling the Joy Machine.
First and foremost though, this is a Kirk book. His friend Kemal Marouk is the Paymaster working for (and against) the Machine, yet another love of his life who we don't get any background for has become a slave to the machine and only he can take a "payday" and save Timshel and the Universe!

Still, I did have to smile when it was revealed that the
Enterprise computer may have had a big hand in defeating the Machine.
That's not to undo the fact that the other members of the
Enterprise crew were sidelined. Spock volunteered to undergo a "payday" and thus free himself from incarceration to work on defeating the machine while Kirk was away, but we didn't see any of this. It would have been nice to see his story.
However, one aspect that did surprise me in this novel was how Uhura was handled and used, perhaps explaining her inclusion on the Cross Cult cover. Despite the rather dodgy dialogue to her "being a woman" and "having a higher pain threshold", we get to see her argue a case with the Joy Machine during the final showdown and have fourth billing next to Kirk, Spock and McCoy, something we probably wouldn't have seen on screen.
To sum up then, traditional
TOS fare with the whole of humanity at risk from a computer who wishes for everyone to feel joy. There were good moments in here, it was good to examine Kirk's friendship with Marouk, but his relationship with Dannie was never given any context and in the end she was completely wasted. Perhaps more threat could have been generated if it was an old flame we had seen such as Areel Shaw or Ruth.