http://www.selkbagusa.com/

I just ordered one of these from Amazon as they are on sale(well maybe not on sale, but $40 cheaper) with free shipping....
Sure looks like it would work nice in and out of the hammock. Ive seen the older version of this , and it looks like some of the shortcomings have been addressed on this newer model.
Plus it comes with a nice compression bag too.

Happy Hangin'
johnny