are they neck pickups realy different from the bridges? dont you just have to turn the pikcup around to lessten the output?
usually on strat the bridge pickup will have slightly more output than the other two. i beleive they have more windings in them, but im not sure.
Bridge and neck pickups don't have to be different, but typically the bridge has more output. And no, flipping a bridge pickup around doesn't make a neck pickup. The output would be the same, but different frequencies would be emphasized.

It all depends on what you're trying to do. If you want to take a guitar and make it a high output metal machine, you can take the bridge pickup, move it to the neck, then add a high output pickup in the bridge. Save some money that way. Of course that's if the two match up well together. Picking pickups can be a fine science if you're trying to get particular tones.
It's a fine line between clever and stupid.