Here are a couple of ways I'm explicitly going to go (or stay) green.
Recycling. We are lucky to have places nearby where we can recycle paper, plastic, glass, metal, electronics, and plastic bags. This almost doesn't count as a new thing, because we're pretty well set up to do these things now.
Freecycling. Again, we're lucky. I don't know if this is an option everywhere, but in our area there is an active freecycle group. Last year I mostly remember the cool stuff we got - a futon mattress and frame, a dresser, a refrigerator. In the past month, though, I've started offering stuff up for freecycle - a loft bed, a violin, electronics. My 2009 goal is to offer up at least one thing per day (on average). I have boxes and boxes of stuff I keep telling myself I should go through. For years. But in my quest to find something else fresh and desirable, I expect to see those boxes dwindle appreciably over the coming year. It would be so nice to be able to actually use the space I own. I'll also get a better sense of what is actually desirable - I mean, if people don't even want it for free, is it worth keeping/donating?
E-gifting. In past we've received large boxes at Christmas time, but no more. This year the gifts we received were modest in size if mailed. In a couple of cases the gifts were hand delivered. Exchanging gift cards? You may say, "What's the point?" I find that knowing we have a gift card or check frees me to get a thing I really want, a thing I wouldn't get if it were just me and my own funds. I figure I'm freeing the recipient from having to exchange items. And if I give a particularly fungible giftcard, they can use it for necessities, if that is really their greatest need. Besides, I've found that's an easy way to help out folks when I become aware of a need. Someone's computer blows up with all their files, someone is in danger of being evicted. I give generously through official channels at work and church, but there are times when you just want to help a particular individual who is down and out. E-gifting lets me do that and extends the potential scope of friends I can help across the globe.
Fight the "Bigger, Better" temptation. I already live in a town home within walking distance of school and (in a stretch) church, and shopping. It's a modest commute from work, which I can do by public transit when not required to drive myself. So I'll remind myself that is good. No salivating over lovely single-family homes that would increase my commute and require that we use a car to do anything and everything. Beyond that there are the decisions about what to do with the home we have. There's a line between necessarily maintenance and "but I *want* a new floor, redesigned fixtures, the thing that will make my house look like that magazine ad." I can embrace the value of 'neat,' 'clean,' 'well-maintained' as sufficient, rather than feeling deprived because I can't gut and trash everything and start fresh. Feel free to tell me other things I should be doing, or that you're doing!