Most of us with fingerprint readers and such devices probably use the software provided by the vendor, to enable biometric OS login or single sign-on functionality. However, I've recently wondered if there is any third-party software that will do the same thing?

This would be similar to how you don't need the manufacturer's software to use a scanner, printer, or webcam - you just use their drivers and your choice of software. Is there anything like this for fingerprint readers or other biometric devices?

Free or Open Source projects are preferred, but I'd be interested in learning about any existing solutions regardless. I personally am particularly interested in Windows-compatible software, but I'll leave the query open for any OS.