I was just in Taipei buying computers when I noticed many of the retailers there were selling "modded" Epson printers. A chip on the quite a few different consumer-level printers had been changed, and these enormous tanks had been glued to the side of the printer. Coming out of the 4 tanks were small clear tubes that joined up in a ribbon-cable style, and ended at the cartridge. Now, I'm not sure if the cartridge was is a special cartridge, because I didnt check, but judging by the popularity of these systems, as they were on display at most shops that sold Epson printers, that they were a good deal long term. I seem to remember that the cost of the printer went up by only about $70 for the modded system. Apparently the retailers could sell you these 500 ml bottles of ink, and thier estimation was that printing costs per page shrunk to %10 of that of what a standard OEM cartridge could deliver.
I wish that I had taken a picture of these modded printers to include, but I neglected to take any. Are these mods sold in North America?