The attic was initially insulated with with two "layers" of stuff. The old layer is vermiculite and then over that, probably installed in the 60's is a layer of shredded condensed Fiberglas. It's really messy stuff (both layers) and the R-value of the composition was calculated to be between 12 and 18. I wanted to add additional R-value while also encapsulating these two layers to limit dust and debris in the attic.
For the insulation, we chose Ultra-Touch, a recycled cotton product. We chose this because we wanted a sustainable option: something that was recycled and as "inert" as possible. We purchased the insulation at the local sustainable building supply store, Greenmaker. This was my first trip there and I am both excited and impressed that we have such a resource at such a relatively close distance from our home. 
I enlisted the help of my friend Steve for the job and we quickly laid down the blanket of new insulation. We didn't have much "thinking" to do for this project and just laid the insulation from wall to wall in the attic. Our ventilation at the eave is already above our attic walls so we didn't even have to worry about blocking these areas.
One note: if you are considering this option, the bundles of insulation are considerably larger than the rolls of Fiberglas you might get at the hardware store. We took two trips and had to use a large vehicle for transport. Also, getting them into the attic would have been pretty much impossible in a house as tiny as ours so we had to cut the stuff open in the living room. It was a little messy but not a big deal.
The result of this work (though it looks neater up there) remains to be seen. I'll have to figure out how to represent an energy audit of the house this winter to observe the effects.
