How to make coffee if you have no filters, machines, devices, or appliances:
Put a 1-2 scoops of ground coffee beans in a mug or tall glass. Add sugar at this point if you use the stuff.
Pour enough boiling water onto the grounds to just wet them, and let stand 30 seconds.
Pour the rest of the boiled water into the mug and stir, or if you have no utensils, tap the mug gently on the counter top, or blow on the grounds at the top to break the surface tension and let the grounds sink to the bottom of the mug.
Wait about 3-5 minutes until the liquid looks clear, enjoy. Do not drink the dregs and don't try to get that last sip before the grounds as you will invariably get some in your mouth, not very nice.
It's very much like a long version of Turkish or Greek coffee, and in Indonesia they traditionally prepare coffee this way, called Kopi Tubruk or 'collision coffee'. There they sometimes boil the two together for 2 minutes, and add sweetened condensed milk for a nice treat.
It makes a great flavourful cup and works fine with all kinds of grinds, from fine to coarse, but best results, as with a French Press, are to be had with a coarser grind.