Well, in Kim Stanley Robinson's Red Mars, the ship consists of tori that rotate to simulate Mars gravity. Of course, this is a very large ship since it's taking an entire colony to Mars.
In Robert Zubrin's The Case for Mars, I think he advocates having a ship that separates into two parts: one for living quarters and one for propulsion, equipment, etc. The two sections are connected by a tether and the whole thing is rotated around the center of mass of the system.
"It's only Neutron. We call him that because he's so positive." --from This Island Earth