Things to share with friends travelling
Books: Take a few short books, and share them amongst yourselves.
Hairdryer/Curling tongs: Have one of each between you.
Extension Lead & Adaptor: Lets you both charge all your appliances and doesn’t hog all the sockets at the hostel.
Money Purse: You and a friend can put an equal amount of money into a joint purse, that will pay for accommodation, excursions and meals. It will eliminate the continuous need to split bills, and just makes paying a lot easier. You can have a separate amount for personal shopping.
Toiletries: If you are travelling for a long time, you may need full sized toiletries, so share the load. You can always pack a spare decanter to take what you need from your friend.
First Aid Kit
Clothes: Rather than take a couple of dresses each, just take one or two and swap with your friend.
Food: Share food shopping and make meals or pack lunches together to keep the cost low.
Phone: Charges abroad can be too expensive. If one of you has a good deal on their contract, then use the one phone to call home, hostels etc. Just make sure you can make emergency calls on your phone incase you need to contact your travelling buddy.
Guidebooks
Washing: Share your washing powder, and if you have a similar colour scheme, you can wash them together.