Where can I download a program which can record sound from my microphone input?

I have done a little bit of recording with Sound Recorder which comes with Windows, but it can only record up to one minute at a time and can only succesfully save in WAVE format. I am looking for a free downloadable program which can record any length of time, and can save in either MP3 or WMA format at 96 or 128 kbps.