The major problem is that colour e-ink displays don't seem to exist - the nearest is http://www.eink.com/display_products_triton.html , which is a monochrome display with a TFT overlay to add the colour.
Way too much.[1] $4700 for a 32 inch color E-ink display right now. $3600 for black and white. $1000 for 13 inch b/w. Everything bigger than e-reader size seems to be insanely expensive.
