OpenSC provides a set of libraries and utilities to access smart cards.
It mainly focuses on cards that support cryptographic operations. It
facilitates their use in security applications such as mail encryption,
authentication, and digital signature. OpenSC implements the PKCS#11
API. Applications supporting this API, such as Mozilla Firefox and
Thunderbird, can use it. OpenSC implements the PKCS#15 standard and
aims to be compatible with every software that does so, too.

Before purchasing any cards, please read carefully documentation in
/usr/share/doc/packages/opensc/wiki/index.html - only some cards are
supported. Not only card type matters, but also card version, card OS
version and preloaded applet. Only subset of possible operations may be
supported for your card. Card initialization may require third party
proprietary software.