Ok, so it isn't going to make you as much money as the Cash for Clunkers plan, but it is a lot easier. What, you ask? Making cash recycling your old ink and toner cartridges at your local office supply store or online.
Depending on where you live, it can be as easy as dropping the cartridges off at your Office Max/Office Depot, Staples, or regional office supply store. $3 per cartridge seems to be the going rate, with most stores putting the money onto your rewards club card to be doled out at a later date. Some stores have limits on how much you can recycle each month, or that you have to make a minimum purchase each month in order to get the recycling credits.
If you don't have a program nearby, look online. You can google "sell cartridges" or try one of these programs: Cash4CartridgesUSA, TonerBuyer.com, Advantage Cartridge, and eCycle Group all offer mail service, and they pay the postage. Prices vary dramatically depending on the type of cartridge being recycled. Unfortunately, all of them that I could find only offer the services to addresses in the continental United States. (Let me know if you know of companies that work outside the US.)
If you are overseas, check on the local economy to see if a similar service is offered, or you might have to send them home to a friend or relative to have them recycle them for you. Depending on your location, you might find that you can earn a lot more or a lot less on the local economy.
While it isn't going to finance a vacation, the money sure does help pay for all the office stuff our family uses. I'm always pleasantly surprised when I get my quarterly gift card with a few dollars on it. It is more environmentally friendly than throwing them away, and it will help stretch your dollars as well.