One of my fond memories of the Marine Corps were the MREs we fought over in the field. Yeah you heard me right, we fought over them. It got to the point that we all had our favorites and when it came time for chow, it was like a pack of wolves descending on an Elk for dinner. We did some dumb shit with the MREs, such as making an MRE bomb using the MRE heater sleeve, a plastic bottle and some tabasco sauce (also in the MRE).
On the more productive side of things is using whats left of the MRE as a resource. In this case as a water collection device. Water is life and in a survival situation you need to be able to think outside the box. If you happen to have an MRE in your pack, then you have a way of collecting rain water. Check out the following video as this former Marine shows you a quick tip on using the outer plastic sleeve to collect rain water.
Photo courtesy of Corporals Corner Youtube Page