You want poop?  I'll give you poop.  I just got back from a Maine Island Trail Association kayak trip. We stayed on uninhabited islands and camped back-pack style except for one thing.  We had to pack out ALL that we brought.  Yep.  Poop included.
We used this:
http://www.amazon.com/GTS-Boom-Box-Toilet/dp/B00030NLNAI was the proud carrier of said boom box and I also had the honor of emptying it at the end of the trip.  It wasn't so bad carrying it until the day the wind was at my back on a hot sunny day and it "burped".  The real pleasure was emptying 6 days of 6 peoples poop in to a port-a-john when the trip was over.  The smell was.......exquisite and I actually forgot to take a deep breath before I went it.  It was downright painful......
I just read that the boom box has a 20 user day rating.  We had 36 user days.  Think about that.......
That's more poop than any man should bear. 
The trip was awesome though.