If you want some cool ideas for guitar electronics set-ups, check out http://www.guitarnuts.com
- they are presented as modifications to Fender Strats, but you could take the ideas and use them to build your own pickup configurations.
From what pitifully minute knowledge I have of electronics in musical instruments (actually, electronics in general), out-of-phase translates to noise reduction. Apparently, in a Fender Strat, pickup switch positions 2 (neck & middle) and 4 (middle and neck) are out-of-phase as a result of the way Fender wires their pickups. And you'll notice that those two positions produce less hum than positions 1, 3 or 5.
(Or maybe I mean in-phase, not out-of-phase?)
Where's Jon68 when you need him?