Plenty of interesting ideas in here, but I have simplified even more than a french press. All a press is, is a way to screen out your coffee grinds after it steeps for a few minutes. So, I just throw my grounds in the pot after it boils, let it steep for a few minutes or however long, let the grounds settle some, then pour it through a mesh filter into my cup. If you really travel light, most grounds settle out and you can just pour the coffee right into a cup anyway with no filter.
When I do this, if I want the coffee to brew a bit longer, I might keep it closer to the flame so it stays warmer and brews stronger for a few minutes, but I don't brew it much longer than 5 minutes anyway.
There are any number of mesh filters, or plastic filter cones that take a paper filter that you can use. Coffee grounds in hot water is the same whether you have a french press or a percolator. You just have to filter it a bit as you pour it out. If you want to have a few cups of coffee over the next hour, just pour it through your filter into a separate pot unless you like it getting super strong and bitter as it steeps for an hour.
Granted, it's not so fool proof and simple as a keurig, but it is not rocket science either, and if you keep an eye on it, you can still make decent coffee. If you use a cone with paper filters, it will be just as clear as your drip coffee at home. Mesh filter let a little bit of sediment through, but at least you don't have to carry anything extra.
On a different note, even when you pre-filter water in the field, you must know that in an hour or so even muddy water will have most particles settle out in an hour, and you can pour off the much cleaner water easily. Of course you should still filter and treat accordingly, but let gravity do it's thing when you can. I'm not advocating drinking from muddy water, just that particles naturally settle out, making the next steps in filtering easier.
ETA: I know the OP asked for a French Press, but we're putting simpler suggestions out there. Chris' example below is spot on and works.
Quoted:
Ehhh, neat, but if you're going to go to that trouble, just get one of those metal cone filters, a SS wide mouth container and two mugs.
Boil 20oz of water in the SS container, remove from fire for 30 seconds (200*,) take 25gm (6 rounded Tbs) of ground coffee and put it in the SS container, stir for 4 minutes, take cone filter and place over 10oz mugs and pour coffee into them.
Clean SS container and tap out filter and rinse.
You'll have a grand tasting cup of Joe with minimal fuss and clean up.
Chris
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