I don't think I could power it through the pedal, because somehow the power would have to get form the pedal to the guitar, and patch cables don't carry nearly enough voltage.
I'm thinking of getting active pickups, so they might have to run off a battery...but I also want this to be flexible. So I could use them even if I didn't have active pickups, or if I didn't have a pedal. I want them to be totally independent of any other parts.
Thankyou both for sharing your thoughts though, I really appreciate it.