According to boingboing.net:
Chicago Tribune reports on how large retailers such as OfficeMax and Walgreens
are offering on-premises ink-jet cartridge refilling services. Hewlett-Packard is pretending not to care, but the article says printer supplies account for about 70 of HP's printer business profits, and that 15-20 percent of the supply business has already moved to third-party refillers.
This would naturally hurt sales of new cartridges. Well that's the way the inkjet crumbles. :) Here's more.