A lot of backpackers really like having coffee in the morning. In fact, I have friends who are so fanatical about it that they roast there own coffee at home and bring coffee presses to make it on the trail. I like hiking with them because they're willing to carry all this extra gear, but when I'm out hiking solo, I either abstain or bring along one of the lighter weight alternatives listed below. Most of these options provide less caffeine than the 65-120 mg provided in a cup of fresh brewed coffee and you'll need to consume multiple servings to get the same buzz you get at home or at Starbucks.
Taster's Choice single serving packs are currently my favorite way to bring coffee on the trail. In the past, I've brought instant coffee in a small ziploc sandwich bag, but that tends to solidify into a solid lump after a while from humidity. Instead, I like the packets because they stay fresh over a long period of time and they take up very little space in my food bag. The Taster's Choice packets also create virtually no waste since the packets are small tubes the size of designer sugar packs. A single packet of Taster's Choice contains 65 mg of caffeine and costs about $0.20.
Before I discovered Taster's Choice packets, I used Folgers' Coffee Singles. These are individually wrapped tea bags that are filled with ground coffee instead of tea. You drop them in a pot of boiling water and let them steep. They produce very good tasting coffee and the wet coffee bag can be used as a scouring pad to clean out your pots after you cook up a meal. The only problem then is that you're left with this sopping wet coffee bag that you have to hump out with the rest of your trash. A single serving costs about $0.35. These deliver about 115 mg of caffeine, depending on how long you let them soak.
Stok (pronounced Stoke) is a relative newcomer to the coffee scene and I just discovered them in the supermarket a few weeks ago. Unlike Taster's Choice or Folger's, Stok delivers its coffee punch in a liquid form. Each box of stok contains 24 individually packaged coffee shots, packaged in small plastic containers the size of half & half cups. Stok is design to be added to an existing cup of coffee, but you can, in desperation, suck them down cold. A single serving contains 40 mg of caffiene and comes in pre-sweetened and unsweetened flavors. If you're going to shoot these straight. I'd recommend the sweetened ones. Cost per serving is about $0.40.
Finally, Java Juice is a favorite with many of my backpacking friends and packs an astonishing 140 mg of caffeine at a cost of about $1.30 per serving. You can drink it hot or cold and just need to add 12 oz of water to it. Each packet weighs just half an ounce and contains water and concentrated coffee, nothing else. Taste wise, Java Juice provides you with an excellent coffee experience and is definitely worth a try if you crave a big jolt. It also has a shelf life of about a year.
Java Juice is not sold in supermarkets, unlike Taster's Choice, Folgers or Stok. REI is probably the largest online retailer of Java Juice, but it is also carried by a lot of local backpacking gear outfitters.