6. Disposable Lighter
High-quality lighters are forbidden on airplanes, but you can put a disposable one in your luggage. The BIC brand typically offers the best quality for disposable lighters, so they are worth the extra cost.
Always double-check any lighter before you pack it, though, as it is possible that these inexpensive items will not work as intended. The perk of having a disposable lighter with you is that you can use it to start a fire. Additionally, it will give you a temporary source of light if you find yourself in blackout conditions.