I'm an "ounces nut" and on most trips (3-5 days) I carry a UST folding stove. Cost be <$15 with fuel and weighs <5oz (again with fuel for 3-5 days). It's not ideal for longer trips or if you have to do more than heat 1pt of water (standard Mountain House meal task). But if you're trying to stay light, it's a nice option for simpler needs.