Epson has released a printer with refillable ink reservoirs. The original article is behind a paywall, so I've reposted it here:

http://52midnight.com/tmp/Epson_refillable_printer.html

The downside is having to pay the REAL cost of the printer, instead of an unrealistic discount to encourage purchase, after which you pay $$$$$$$ for ink. The reason is simple. This widely-practised quasi-criminal marketing ploy has been defeated by the ready availability of cut-price ink cartridges from Third World suppliers.

But is the new printer Linux-friendly? Any takers or willing guinea-pigs?

I almost bought one that had a sort of wax candle for refillable ink. I think they figured out it was too cheap to operate.

Isn't there some printers now that use bottles?

I'd assume it has some standard, some sharp linux coder would have to make a file or way to use it for sure.

AFAIK this has been hacked onto a fair amount of Epson printers. Just search for "Epson CISS" (Continuous Ink Supply System)