A charity called "Parley" has created a system where plastics are recaptured from oceans around the world, and turned into a premium alternative to new “virgin” plastic, thus reducing waste and helping to clean up the oceans.
Their plastic is used by companies like American Express and Adidas.
Maybe something for giffgaff to look into? I believe the SIM cards are made of plastic?
How did I come up with the idea? I browsed the internet.