Just wanted to follow up on your comment and link to a few older comments where I expand on how I do this.
The basic premise is that I try to live off of society's excesses without pulling new things out of the supply chain. So I tend to sleep in public spaces, eat food that's left over from others, wear hand-me-down clothes or "shop" in free stores, and so on. When I need to travel, I ask around for someone driving the same way.
For a few areas of my life, I still need new things, such as web hosting, occasional bus ticket, etc. For this, I allow others to interface with the currency system for me, and contribute to them in other ways, such as helping them with whatever they need help with.
As far as the bigger picture, I contribute by constantly looking for and doing things which need help doing, such as: cleaning up trash where it's not cleaned up, lending an ear to someone who needs to talk, teaching what I know to others, and so on.
I really resonate with the Steve Jobs quote that everything (man-made) around us was created by someone who had less knowledge and understanding of the world than we do today (because they did it in the past) and there's every reason to believe that each of us can do better if we put our mind to it.
I started at being all-currency, the typical job-apartment-cat type scenario, and I gradually found replacements for each things I needed to function, sometimes with an uncomfortable transition in between.
If you want details, there are some in my comment history.
Initially, I set out to have more time for my passion projects, which meant spending less time working for money, which, in turn, meant lowering my upkeep costs. I started unsubscribing from one thing, and then another, until, one day, I noticed that it has been days or weeks since I'd used money.
I wondered if anyone else was doing this thing, and I found freganism, "The Man Who Gave Up Money", etc.
And digging deeper into this, I realized several things after pondering them for a while:
a) I'm now operating in large part on my karma, and using money is almost always a karma negative. When I exchange one dollar for something, I'm setting in motion a whole chain of events to which I am karmically connected, most of which are negative.
b) When I work for money, all I get is the money. If I work for an employer for five years, all I have at the end of those five years is the money, which I am, honestly, not capable of managing well, something I have accepted about myself after so many years. On the other hand, if I abandon money, I have time to work on my relationships, something which pays infinitely better.
