Have you tried coffee bags? You can get them at the grocery store in a box of about dozen or so. They are more expensive per cup than regular coffee, but are very easy to pack. Each bag is in an individual foil wraper. Just bring water to a boil, remove from heat, drop in a bag (just like a tea bag) and let it sit for a few minutes.

Also, as I travel and stay in motels, some of these have little 2-cup coffee makers that use a small filter pack. Same deal. Drop one of these in two cups of boiling water and fish it out in a few minutes.

You can also use the larger filter packs that are supposed to be used in a drip coffee maker in a larger pot. But, be careful as you fish it out. The larger bags tear easy.