Omnikey CardMan 3121 USB CCID reader
The Omnikey CardMan 3121 is a USB smart card reader.
It is compatible with the USB CCID class device specification and can be used without any vendor drivers by Free / Open Source software such as libccid and OpenCT. Having said that, it of course also works with vendor-supplied PC/SC drivers on Windows, as well as Mac OS X.
The Omnikey CardMan 3121 offers a single full-sized card slot. So please make sure to obtain a mechanical adapter separately if you want to use it with plug-in sized SIM cards.