A Water Purifying Bottle: If you're travelling to a place which doesn't have the cleanest water to drink and you rely on packaged drinking water, these will be your best friends. You can also use it as an alternative to a reusable bottle.
Your Own Cutlery: Carry a stainless steel travelers set. Not only it is eco-friendly redusing the use of plastic, it is also more hygienic.
Menstrual Cups: If you worry about packing tampons and sanitary napkins, these cups are eco-friendly and you can even swim if you are on your period. How great! Other alternatives are period panties and reusable sanitary pads!
Stainless Steel Containers: These 'dabbas' are a great way to avoid taking leftovers to your hotel. They are eco-friendly, reusbale and you can avoid plastic packaging for your food.
Microfibre towels: Not only are they easy to dry and use, they are eco-friendly. So pack your own for that green holiday!