Several years ago I spent a few weeks in a country that as far as I could tell didn't have a "coffee culture" and all that was readily available was packets of instant coffee. I hunted around and found a vacuum packed brick of ground coffee at a shop, but didn't have any equipment to brew it. Then I worked out that you can throw some in a glass bottle, pour in some hot water from the kettle, let it sit until everything settled to the bottom, pour out the liquid, and "voila!"

Later on the trip I bought a Turkish coffee maker, which works on the same principle, so it's not so much an innovation as it is a hotel survival tip.

Cowboy-coffee is just a pot with water and coffee grounds on a fire. Apparently there is a trick involving adding egg-shells to the grounds to make them settle more quickly (never tried it, though).

Glad you prevailed! My nightmare scenario is having coffee, but no way to grind it.

Beat the coffee grounds into an egg while bringing water to a boil, then get the whole mass into the water. Can boil for an extended time (say 3-5 minutes) and use old stale coffee and it will improve the flavor and keep the grounds suspended in the boiled egg making the pour off easy.

That's a very common misconception. The egg shells are for their calcium carbonate, in order to cut down acidity and improve the flavor. The classic trick to causing the grounds to settle quickly is simply to add a little bit of cold water at the end of brewing.

The egg whites that remain on the shells also acts as a flocculant for suspended solids.

The trick for that is to use two identical bowls, one as a mortar and the other as a pestal.

This is the best way to do a French press too. Pushing the plunger all the way down just disturbs the grounds that have already settled. Better to keep the screen at the top of the liquid level then pour out slowly.

And the cupping procedure doesn't even do that, but still produces reliable tasty cups.

Oh. I thought you were going to say centrifuge