The first thing that comes to my mind is NFT. It’s a non-fungible token. This is a pretty popular thing these days and many companies start using it. First artists used it to protect their copyrights now it’s discovered it has many features. For example, this startup https://myimpactpower.org/ sets a goal of making people friendlier to the environment via various challenges and not only. So, to fund themselves, they started selling NFT cards today. You can check them and if you support eco-activism then buy them.