Richard:
Quick answer is whatever siding I don't have to paint/stain/protect ever again....
I finally listened to Em.. it wasn't what I wanted.. as I never liked vinyl siding.. but.. and this is a big but.. vinyl has improved 1,000% over the last 35 years or so.. and when combined with other finishes, it does provide a good, relatively maintenance free cladding.
I used 2x6's which were then wrapped in brown aluminum to essentially block in the building, delinieate floors, meld with the facia and soffit finish which is brown aluminum and of course the capping where needed on fixture pads such as light, doorbell, hose bib and other pads. I then finished with a cream vinyl siding. Looks really nice.. easy on the pocket book in relation to other finishes.
I intend to finish my shop and pole barn extension to my shop in the same fashion.. it will match the house.
It worked out well. You can see pics of the house on the server in the My Cubs section of the Gallery.. it does look pretty good and goes well with the decking as well.
Other points.. even if you are heating with a wood stove.. INSULATE, INSULATE, INSULATE.. keeps you warm in the winter and cool in the summer... trust me on this one.. you do not want to NOT INSULATE.. even if you just put in a single layer of R-12 for this year.. you can add another layer of R -12 batts or even R-20 or greater as needed.
Also, make sure that you use a building wrap such as Tyvek.. you WILL be glad you did..
Don't use OSB for a finish ok.. and no you may NOT ask why I said that