I am building a super-insulated wall with two layers of foam on the outside of my stud wall, then installing a proper drainage plane using vertcal 1x4 furring. Next I want to install siding. All literature shows horizontally placed siding, but I want vertical. Does this mean I have to strap the walls again horizontally?? What if I install the layer of furring horizontally and make small sawcuts every foot to create a drainage plane?  Any ideas are appreciated, I certainly don't want two layers of furring.

You could use galvanized steel furring strips 1" deep made in a zee configuration. Mount them horizontally and have the leg of the zee that meets the siding pointing down to allow for drainage. Attach the siding to the zee with self drilling sheet metal screws. Would also use a weather barrier between the zee and the sheathing and seal any screws into the sheathing with mastic.

You could cut slots in the strapping or use "cedarbreather" or "greenguard" on either side of the strapping. Alternatively, there is doubt whether providing for "drainage" is really necessary. Most houses built to date without rainscreens and with rot or moisture problems don't rot due to running water at the sheathing, but from long term damage by water vapor. (not to say it never happens). The rainscreen, drainable or not, will keep the siding away from the sheathing and allow air to get to the backside of the siding, prolonging it's life and the life of it's coating.