Re an octave pedal:
I don't tell anyone this, but I use a Boss OC3 Super Octave pedal on my pedal board.
This newer development in Boss pedals has a Polyphonic control that allows you to select which strings you want to "Octavize".
Typically I use this to play bass on the low E and A strings with a hint of octave bass on the D (standard tuning).
When you're playing chords it's important that you don't hit both octavized strings together. For instance: an F#m chord played on the second fret would sound muddy, or a bm chord where you played the f# in the barre. You have to adjust your technique in playing these chords, or find other voices that you would prefer to use up the neck.
In order to effectively use this pedal you need a subwoofer in the system, otherwise you won't even hear the octaves. The pedal takes a bit of dialing in, but once you've gotten to the sound you want - it's amazing.
My pedal string is: guitar to-
Baggs Para EQ
Ernie Ball JR volume pedal split with planet waves stomp tuner
Super Octave Pedal http://www.bossus.com/gear/productdetails.php?ProductId=608
RC 20xl looper double pedal (so I can play guitar and flute at the same time)
to Radial JDI direct box
I use this set-up live all the time. All of the components are Boss except for the power - Visual one spot, Ernie Ball volume pedal, Planet Waves tuner, and the Baggs para EQ. All my acoustic guitars use Baggs M1 Active pick-ups. They all have on board electronics, too, but they are inferior to the Baggs M1 Active, which is an outstanding acoustic guitar pick-up when used with the Baggs Para EQ - a DI equalizer.