One of the techniques of lightweight backpacking is to use items that perform multiple functions so that you end up using less gear which can significant lower your base pack weight.

You can either use your poncho as a tarp tent or a groundsheet but not both at the same time. Heavy ponchos have grommets along their edges so it's only a matter of stringing them up with nylon cord.

Lightweight ponchos on the other lack grommets so be sure you have them inserted before your backpacking trip if you intend to use it as a tarp tent as well.

There are many ways you can set up your tarp tent and there are other uses of the poncho as well. You can use it as a pack cover, vestibule, emergency bivy, gear hammock, water bag, packraft sail, parachute for your pack and even as a sink for cleaning up your dishes.

A multi-tool like a Victorinox knife or a Leatherman have many functions including as a knife, pliers, scissors, saw, tweezers, toothpick, file, flashlight and more depending on the model. Though most of the tools rarely ever gets used, they might prove to be useful when you need to make repairs.

There are at least 75 uses of baking soda including as a deodorant, toothpaste, cleaner, mouthwash and more. They can also be used to treat bug bites, bee stings and relieve acid indigestion or heartburn.

There are many other possible uses of baking soda but just having baking soda in your backpack won't be very useful unless you know how to use it.

This wonderful piece of stretchy cloth can replace your bandana. It does what the bandana can do, only better. You can use it as a headband, bandana, neck scarf, handkerchief, face mask, balaclava, scrunchy, emergency water filter, emergency coffee maker and more. There are no seams so they're comfortable enough to sleep in during cold nights.

A rope has many uses but the MILSPEC has the strength of a thick rope without the thickness. It's the most versatile cord you'll ever use. You can use it to set up your poncho tarp tent, as a fishing line, for hanging clothes and bear bag, making animal snares, and many others. You'll see why this is trusted and used by the military.

The duct tape has often been used to fix everything but it also has applications in first-aid. It's probably the most important repair item.

Trekking poles can be used as a tent pole, camera stand (not all trekking poles), defense against snakes and wild animals and more. Use it to stabilize your hiking pack and you have something to lean on. There are surprisingly many other uses of trekking poles.

A camping mattress can be converted into a chair and a sink (combined with a poncho), used as a frame for ultralight packs and kneeling pad. At home you can use it as an exercise mat if it's a closed-cell foam pad.

The tent-cot is a combination of tent and a cot. It's pretty cool but too heavy for backpacking. It would probably be nice for car camping.