For a nominal 30 dollars you get control over mass mailed catalogs shipped to your address and if that in itself is not sufficient incentive you get 5 trees planted in your name for the first five opt out requests.

Here is a video by Green Dimes explaining their offering.

1. For starters, switch off your computers, printers, monitors when you leave after work. While you are at it switch the room/cube light as well. This in addition to saving energy should also help your company cut costs and hopefully your company stock should go up as well. And it might just reduce some heat that is generated collectively by all the computers that would otherwise be running. My previous employer Oracle had sensors installed at each desk to sense and automatically switch off the monitors and lights in the cubicles. These were installed during the infamous California blackouts few years ago. I am sure many of the Calif based companies did the same.
2. Set your printers to print dual sided print-outs. Most of the newer printers allow you to do print dual sided. If you are not one of those with thick eye-glasses, you can also print more than one pages per sheet. When you are printing those flashy Powerpoint slides for review/as handouts, make sure that you have set the “Color/grayscale” setting to “Pure Black and White”. This will save you from getting those dark slides which will render those documents unreadable and also kill the toner and use more energy on the printer.
3. Here is something I did and so did many of my colleagues. If for some reason you cannot print dual sided or you had one of those runaway jobs that printed a ream of paper that is not useful anymore, use the backside of those sheets of paper for your rough work.
4. I recently read about a company in NY where employees stopped using bottled water and used the tap water instead. Besides cutting costs for the company it also reduced the amount of plastic that was potentially going into the environment. If your company is looking to reduce costs, this is a low hanging fruit.
5. Recycle the cellphone, pager (does anyone use them anymore?), iPod, iPhone, Blackberry batteries when they are used. If you company does not provide locations on campus to dispose the batteries, request your facilities for one (or even better one for each building). I am sure they will be more than happy to provide one.
6. Carpool to work if possible. I know with all the crazy work schedules people follow, it is tough to find someone whose timings match with yours but even if you can carpool few days of the week it would help. Check with your employer to see if you can telecommute atleast on days when you have no meetings and do not have to manage anyone.
7. If you are traveling to a place where there is alternate mode of mass transit like buses and trains, see if you can adjust your work schedule and make use of those modes of transport. This will save you a lot of energy you expend when stuck in traffic getting frustrated. And… You might just be able to review that document that you could not find time for while using the mass transmit. Certain parts of the country have the “Spare the Air” programs on certain days of the year when the mass transit is free. San Francisco has one. http://www.sparetheair.org/. Make use of these opportunities to not drive.