Oooh, good subject!
For light aircraft, I tend to side with the "none or optional" crowd. Personally, I do a methodical but reasonably rapid scan around the cockpit to make sure that the important knobs and levers are in the required position, like Backpacker above. I try to look at things as though I'd never seen them before and think: "how should XXX be set up for this stage of flight?" as an open question.
In the airline world, checklists form an important part of the operation but they are not infallible, even when being used by two (or more) people. It's relatively easy, in challenge-and-response, to respond with what you *expect* to see (or what is normal and you've got very used to seeing) rather than what is *actually there*. I've witnessed similar things happen with solo checklists in GA, when the checklist overrides reality!
IMHO going over in your own mind how you are going to operate the aircraft, be it normally or in an emergency, *before* you actually go aviating, is worth a thousand checklists...