Somehow I ended up ordering the Hakko FX-901 battery operated iron. I think it snuck into my cart with some books I was buying online. Anyway I got it and it actually works alright. 4 AA batteries give it power for about 60 minutes. Enough to do a bit of soldering anyway. It heats up to a good temp and solders well, but it doesn't seem to recover very quickly. Which of course it wouldn't, its only a 7W iron.
Anyway, for doing a few small soldering tasks out in the field I would recommend it. But if I was going to spend more then fifteen minutes soldering I would seriously think about going back to the shop.
Its pretty well built. Good solid feeling plastic. The switch is a bit cheap buts its only a $30 iron. It does end up being cheaper then the butane powered alternatives, so I'm keeping it. I can post a video of it sometime if people are interested.