ZIllions. From the top of my head, and in addition to the above:
- compressed air tank (used 2 for DIY snuba device, can be used for improvising the energy source for the pneumatic instrument as well, as it holds up to 150 PSI);
- cut out 4 spoons;
- plants auto watering device;
- plants manual watering can;
- automatic animal feeder (grain/water);
- attach to a tree for a camp hand/face washing station;
- air/water pump (suck or blow);
- water distiller (put green leaves inside);
- plastic is hot-shrinking (apply heat over the plastic ties to tighten them);
- plastic of the bottle and of the cap can be melted to make seals, used as a glue, formed into hard plastic things, used to repair holes;
- the top screw with the cap can be used to seal plastic bags, make tarp attachment points, gather ends of fabric;
- cut out a grain/flour scoop;
- make long air/water pipes (cut ends, stack, shrink/melt joints);
- firestarter (water lens);
- camera "tripod" (1/4x20 screw in the cap, sand/water in the bottle);
- shoes (cut an entrance or flatten and add straps);
- sleeping bag warmer (feel with hot water, wrap in clothes, hug it);
- neck pillow;
- flashlight mount/stand/headband/diffuser;
- fishing bobber, fishing net floats;
- knee/elbow abrasion protection;
- safety glasses;
- smoke mask;