One way to do it is to send them back to the manufacturers for either re-use, or proper disposal. And the manufacturers are starting to make it easier for you to do that by offering returnable cartridges, at a lower cost.
If ecology is something you're concerned about, then when you are buying a new printer, you may want to see if there are returnable cartridges available for that particular printer. How can you tell? It's now always easy. If returnable cartridges aren't mentioned on the printer's product page on the manufacturer's Web site, the next place to look is on the part of the site where cartridges are sold. (Almost all manufacturer Web sites have them now.) Look for the Supplies link -- which could be either on the product page itself, or in its own area on the site -- and see if any returnable cartridges are being sold.
You won't only be doing your ecological bit, but you'll save yourself a few dolllars besides.
