If you have´t yet heard of or tried beeswax wraps you should set that as a goal for this coming week. Locate the nearest / easiest place to purchase them and start wrapping your food leftovers or sandwich.
Beeswax wraps are made of cotton / linen cloth covered in beeswax which makes the cloth wrap-able. It is much much better than using single use plastic or foil pluss it looks way nicer, especially bringing your sandwich to work in a cute little wrapping cloth.