At home I have a spray bottle with a bit of sweet mandarin and tea tree oil in water, but when it's cold I have a small bowl and one of those small stainless steel thermoses, like you get at vietnamese/chinese restaurants, with the pop-top button. I fill that up with hot water once a day usually and just pour a splash onto a wipe and wring out the excess into the bowl (which I use to water a pot-plant later!). It's nice to have warm water for cleaning up little bottoms here in winter! If I'm going out, I have a mini thermos for the same thing, or a small atomiser that I picked up from an asian grocery store. I dont have a nappy bag, just a folding change mat and a couple of wetbags that are thrown into whatever bag I'm taking with me! One for clean stuff, ond the other for dirty.