I'm like Alan and drink coffee all day long. Maybe at least 2 pots? lol ... It beats drinking 2 pots of whiskey like I used to do 15 years ago. Talk about headaches Joe. Although I didn't have too much trouble going to sleep back then.
I also have that Coleman camp stove coffee maker. It's been working great for 3 years now. Although I've melted some of the plastic up top on it now. Just don't touch the base of it! I've made my share of cowboy coffee too, and the eggshells do seem to work. Or maybe I just don't know the difference anymore?
IMO, it's best to keep a spare coffee maker (or two) for emergencies in case yours breaks down.