A feature the Yubi has over a smartcard is the button. You can get smartcard readers with pinpads etc, but not that fit into an Expresscard slot.

I was pretty close to getting a Yubi, until I realized that the default version couldn't modify the PGP applet, and didn't find exactly where to order the special "developer edition" either.

At this point it probably makes more sense to find/make a dongle based on an STM32 or the like. The problems with non-hardened hardware discussed in the article are real, but I'd bet the features/innovation enabled by a Free design will outweigh those tradeoffs (eg an audit log, indication of what you're signing/unlocking, actual encrypted key material when the device is "cold").

It's a unique product in the sense that it has nice form factor and holds additional functionality for more main stream uses. I have a number of these devices, including the external card reader, the usb key card reader and the integrated rubber usb key. Everyone can decide what they want of course, just don't be surprised when they discontinue the NEO.

If you read between the lines of how it went from closed, to very open, to less open, to now not open at all. It seems like they tried open source but failed. They were probably looking for people to integrate it into some e-mail client, chat application or even bitcoin wallet. Now they've gone back to focus on their core customer and using a cheaper more integrated chip.

Feitian has a similar product with known keys and running JavaCard in the form of an USB token - http://www.ftsafe.com/product/epass/eJavaToken . Also much cheaper than the Yubikey, see http://javacardos.com/store/smartcard_eJavaToken.php . No NXP proprietary stuff on it and no NDA required either.

I use pgp on my mobile devices too, I would prefer something I could use for both my phone and my computer. The NEO would have filled that role. In my research I haven't found anything like that so far. I would love to be enlightened though if anyone knows about something that can do the same!