On Wed, Aug 17, 2016 at 2:14 AM, Peter Todd via bitcoin-dev <bitcoin-dev@lists.linuxfoundation.org> wrote:

I'm not aware of any ECC-enabled smart-cards that can sign the specific curve
that Bitcoin uses, not to mention the fact that those smartcards generally only
speak higher level protocols than raw signature generation, precluding the
signing of bitcoin transactions.

any Java Card supporting ECC can sign on user supplied Weierstrass curve parameters - you can find a good shopping list at http://www.fi.muni.cz/~xsvenda/jcsupport.html (look for ALG_ECDSA_SHA256 on javacard.crypto.signature). The NXP JCOP platform (found in Yubico Neo) is a popular choice, and then you can add your own custom logic for validation.

Nicolas Bacca | CTO, Ledger