- You can use it as a poncho if you cut armholes and a hole for your head
- Fill it with air, tie it up, and use it for a float
- Cut it into pieces for several solar stills
- Waterproof the roof of your shelter
- Cut it down the center, run a line between two posts, and you can use it as a tent
- Put your pack in a garbage bag to waterproof it
- Fill a garbage bag with water, seal the bag, and place it in the sun. The bag will act like a water heater.
Here's a few more ideas