Ran across this on another list:
http://vacworld.bzlogi.hu/minituner/index.html
May possibly be useful.
This is my main tuner for whistles. It works great for whistles, but I find that the harmonic overtones in string instruments (at least tenor banjo and mandolin) confound the input part of the program and I get results that my ear assures me are wrong (usually by 500 hz or more). I thing an aligator clip mic would solve the problem, but I went and got a physical tuner so I could tune away from my computer.