David, I have a question. When Geordi and Guinan were discussing time travel methods, Guinan mentioned the giant donut and I was pretty sure I remembered reading a TNG book with that in. IIRC, it was Requiem where the donut sent Picard back to his Stargazer days. Is that the donut you were referring to?
It's so long since I read that that I don't remember whether it was the GoF or not, but I'm not so sure that it was...
No, in Requiem
they encountered a large toroidal structure in space that functioned as a time portal.