Everyone has old tires that are no longer viable for a vehicle, but don't throw them away. They can still serve the homestead well.
As the price of metals has increased, so too has the value of metal junk. You can sell any old metal, but it is often more efficient if you can use it yourself.
If you can either prevent something from going into a landfill, or go and physically take something out of one, you are helping to reduce the enormous problem that waste has become.
It is inefficient to recycle glass, as it uses so much energy. However, reusing it is practical. Glass is easy to sterilize and has many different uses.
Aluminum cans can be reused or reforged fairly easily at home, and have a multitude of purposes. They also have a resale value, if you want to collect them and earn a little extra cash.
Plastic waste is a bane to the landfills and countryside. However, it can be reused at home in all kinds of different ways. It has the advantage of lasting a long time, making it good for certains types of projects.
Every time you change your truck's oil, you produce a very valuable waste product, most notably as a diesel. Other oils around the house can be used for all srts of things on a homestead.