Yes, I know this is another off-topic posting, but I'm sure more than a
few of you will be interested in this.
It apparently turns out that the Epson 870/890/1270 printers with the
chipped cartridges work by reading the cartridge info once upon
installation, then that info is sent to the computer and then software
is used to keep track of the ink levels until the cartridge is removed,
at which point the new ink level info is written to it.
Someone has figured out a way to trick the printer into thinking a new
cartridge has been installed, while then replacing it with a refilled
one. The only "problem" is you do need to have one Epson full cartridge
for both black and color to "program" the printer with each time you
wish to install a refilled cartridge. It also requires that you remove
the top of the printer to access the areas needed to do so.
Anyway, the instructions are available (the english is a little
difficult to follow as it seems to be second language to the web site
Hope this helps. BTW, there is also a link from MIS inks, who is now
selling refill inks for these models, as well.