I have a pretty standard setup, as represented in this crude drawing I whipped up.
(green are speakers, red are TV and amp, white is furniture)
Two tower speakers at front of room on either side of the TV. Center channel will either be above or below the TV, haven't decided as of yet.
Sub will likely be to the left of the left tower speaker in the front corner of the room.
Two speakers on either wall, then two more in the rear corners.
I've tried to make sure any audio cables are not touching any electrical wiring. Here's a shot of the wiring right now. Notice the grey sub cable running along the bottom.