This is the lowest price ever on Sony's DPT-RP1 digital-paper tablet

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If you've ever thought, "I wish Amazon made a much bigger Kindle, one I could write on with a pen," you're not alone. Such a tablet would be amazing for reading and marking up documents.

Amazon doesn't, but Sony does: The DPT-RP1 is a 13.3-inch E Ink tablet designed expressly for that purpose. It's been on the market for well over a year, but has never dipped below its $700 list price.

Until now: Adorama, Amazon and B&H all have the Sony Digital Paper DPT-RP1 for $599.99 shipped. (My advice: If you live outside New York and New Jersey, bypass Amazon to dodge sales tax.)

Granted, a $100 savings isn't exactly incredible, but the DPT-RP1 simply has not budged from its original price. So any discount is noteworthy -- especially if this is something you can use.

Is it? The tablet is something of a one-trick pony, able to display only DRM-free PDFs. I think that's a pretty huge limitation -- at the very least, how about supporting Word files? -- but if your org lives and dies by the PDF, it might be no big deal.

Actually, this pony does one other trick: markup. Using an included stylus, you can annotate your PDFs: add notes and drawings, highlight text and so on.

I've never used one of these, and ZDNet hasn't reviewed it. Reviews elsewhere seem to run from "favorable" to "mixed." Most of the dings seem to center on the PDF-only file support and the lack of cloud services: You have to sync documents via Sony's desktop app.

It's worth noting that there's at least one other competing product, the Boox Max2. It also has a 13.3-inch E Ink display, but it runs a pared-down version of Android and therefore works well outside Sony's very limited boundaries. Alas, it's $800.

If you've used either of these products, hit the comments and let your fellow markup fans know what you like and don't like.