What kind of emergency snack/meal/drink/tools do you always carry with you in your hack pack? Mine are:

  Drink:

    Yerba mate (dried tea)

    Yerba mate straw
    5-hour-energy or similar

  No-prep snack:

    Nuts or granola bar

  Meal:

    Instant oatmeal packet
    Ramen packet

  Food-related hygiene:

    Folding toothbrush

    Small toothpaste

    Dental floss (doubles as general purpose string)

  Tools:
    Collapsible silicone cup/bowl
    Filtering water bottle

    Spork

    P-38 can opener

    Knife (in multi-tool)

    zip-lock bags

All of the food/drink items have in common that they don't weigh much and don't really go bad. We usually buy these items bulk and re-fill missing item when at home base.