The aluminium (that's how we spell it up here...sometimes) coated, polyester film used in chip bags and many other food packaging is the free equivalent to reflective mylar. Although not designed to have a "mirror finish", it comes close enough for the cost alone.
Think of how much of this stuff you throw away each day simply because it is not recyclable.
We've almost definitely produced enough to cover the planet's surface at least once. If we layed it all shiny side up, would we not be able to reflect the sun's rays back into space and solve Global Warming?
Step 1: What's Good About It?
My favourite source is the plain milk chocolate bar due to it's level of flatness (for reflective surfaces) as well as it's managable size and has nothing at all to do with that sweet, sweet, life giving, coma inducing gift from the God's, chocolate. If larger single pieces are required, chips come in all sizes or tape them together to form a sheet..
Please note that not all packaging is created equal, for varying reasons, and some may suit your need better than others.
Step 2: What You Need
One digestive system (not shown)
A blade or cutter of choice
A need or desire to become part of the solution and less of the problem
Step 3: Recovery
1. Open package carefully, along a glued seam if possible and eat contents.
2. Open into a flat sheet by seperating glued seams and/or cutting away "welded" seams and heat damaged, wrinkled ares.
3. Wash in warm, soapy water, rinse and dry. Be careful to keep as flat as possible for best results.
4. Remove any remaining adhesive with your fingers when dry.
5. Cut away any jagged edges, so that all edges are smooth, to prevent unwanted tearing.
Step 4: Uses
I personally use it to reflect ambient light back toward a window to enhance the natural light for growing plants indoors in the winter or starting seedlings in the spring without additional cost or energy use. I've also started building solar ovens this spring and am using it where heating, or heat sinking, is not an issue.
Most is superior to aluminium foil as a reflector for several reasons.
1. It doesn't wrinkle (much), making it reusable, portable, foldable, rollable, storable and durable while retaining a smooth, mirror like finish. Necessary to focus light.
2. It is tear resistant. Tear resistant holes and edges can be burned through instead of cut.
3. It generally has a higher reflectivity than foil to start with.
It is also useful in a multitude of crafts or anywhere where a one sided, mirrored finish is required. Uses include gift wrap, party decorations, baby's room, floral arrangements and any other crafty idea.
It can be used as a thermal blanket or a tarp. It can be bonded to bubble wrap. You could make reflective, water proof, easily replacable tiles or shingles for use in other projects such as building an emergency reflective shelter with ventilation....
One could..........SAVE THE WORLD!!!!!!