Internet radio kbps limiter?

ok simple as this. seing as internet radio is given out better and better download rates kbps and dont get me wrong this is a good thing but problem is i listen to a lot of radio and have a monthly download limit. so it occured to me there must be a way to limit the kbps you get with some sort of program. i know that in windows media player you can select high or low quality streaming so it seems to me it is already possible. does anyone know of a current method or would they dare to venture into the programming of such a feature themselves ?