Small nitpick: Smart card readers are not platform-specific. I've got one working on Ubuntu with Firefox and it would probably work on OSX as well. I would be surprised to find them not working on Vista.
In addition to Intel, you can also try Atheros chipsets http://madwifi.org/. They're partly binary, but they work very well and are extremely easy to install.
*Note: The Atheros drivers do not support USB chipsets and no plans exist to do so.
Small nitpick: Smart card readers are not platform-specific. I've got one working on Ubuntu with Firefox and it would probably work on OSX as well. I would be surprised to find them not working on Vista.
In addition to Intel, you can also try Atheros chipsets http://madwifi.org/. They're partly binary, but they work very well and are extremely easy to install. *Note: The Atheros drivers do not support USB chipsets and no plans exist to do so.