Apparently this bag lowers the amount of fuel needed to cook drastically for slow cooked items like stews and soups.
anybody ever used anything like this?

http://www.amazon.com/Wonderbag/pages/7599575011/ref=azss_398553662_2?pf_rd_m=ATVPDKIKX0DER&pf_rd_s=center-5&pf_rd_r=1V35QW8AARPWZJGFF0BN&pf_rd_t=1401&pf_rd_p=1933370222&pf_rd_i=1002990081

the videos make this look like a winner. you can bring pots to a boil on a rocket stove, and place in this.

Never seen this product before but have heard of similar techniques for making stews.  In  episode of I think "Wartime Kitchen and Garden" they made a stew by bringing it to a roaring boil then placing it in a wooden box stuffed full of hay then wrapping it in an old quilt.

did a little Googling to try and find the episode, turns out it was in Wartime Farm (Episode 2).  You can find it on youtube at 26:50 then opened at 36:00 Video Link

I also found some more info on "Haybox" cooking on Wikipedia it also has a link to a wiki article for the Wonderbag at the bottom of the article.  WIKI link

camping ive done the whole zip lock with hot h20 with dehydrated soups,,shoved in a wine bootle coozie  and let it sit while i did other stuff.

I'm all for prep-related ideas going mainstream, I really am; but that's absurd.

For $57, you get the equivalent of a folded-up blanket or quilt. Cool.

So what's the advantage to a bag over a good ice chest. I know people traditionally use them for "ice", but wouldn't it trap heat just as well?