Meet the Digital Paper, Sony’s latest e-ink slate. It’s part iPad, part e-reader, and must be made out of moon rocks. It’s $1,100 and will be available in the States this May. But you’re not going to buy it.

The 13.3-inch “letter size” Digital Paper isn’t for the average consumer. It’s definitely not for me. Sony is marketing it to gullible legal professionals with large expense accounts. It’s a note-taking device. The flexible e-ink display boasts both optical and active digitizer touchscreens allowing for finger and stylus input. Markup documents right on the screen. Files are saved in a repository that can be shared.

It’s too bad that the software only supports PDFs.

Sony introduced this device to the Japanese market last year. Since launch the device has only supported the editing and viewing of PDF documents. Word and Excel docs can be converted to be viewed on the device. But it’s still a PDF. And as the Digital Reader notes, it lacks an email client and the ability to install additional software. What you see is what you get.

The device sports Wi-Fi, 2.8GB of flash storage, a microSD card slot and a 13.3-inch flexible e-ink screen with a 1600×1200 resolution. The battery lasts three weeks. The whole package is only 6.8mm and weighs 358 grams — that’s less than half that of the iPad air.

Digital Paper will be sold in the U.S. this May through Worldox, a U.S.-based company specializing in document management for legal professionals. Maybe I don’t get it. I’m not a legal professional, and I’ll stick to my iPad for note taking.