I've found https://wiki.debian.org/Smartcards/OpenPGP a really good resource with plenty of links. There's also https://www.gnupg.org/howtos/card-howto/en/smartcard-howto-s... & http://www.narf.ssji.net/~shtrom/wiki/tips/openpgpsmartcard which I've found helpful. Once they're set up they behave just as if the key was part of your local keyring encrypted with the smartcard's passphrase, but is of course only usable when the card is plugged in.

It actually seems like the Yubikey Neo also supports GPG, so that is quite nice. I own http://shop.kernelconcepts.de/product_info.php?products_id=4... & http://shop.kernelconcepts.de/product_info.php?products_id=1...