Consumer interest in e-paper pretty much got killed entirely by the tablet hype but some companies are still pushing forward. Sony for instance just announced that its 13.3" Digital Paper device will hit the market in May for $1,100.
Digital Paper features a semi-flexible A4-sized E Ink Mobius display with support for stylus input. The screen has a resolution of 1600 x 1200 pixels and supports 16 levels of grayscale. WiFi support is included, as well as 4GB internal flash memory and a microSD memory card slot. Sony promises a battery life of up to three weeks on a single charge.
Sony markets the 357g light-weight device for educational, business and legal environments. Besides the high price tag, one other important drawback is that it appears to only support PDF, but you can convert Office documents to PDF format.