Audio Normalization Script for Python/ffmpeg. I've only tested it with Python 2.6, not Python 3.
The script normalizes media files to -26 dB RMS. It outputs PCM WAV files named as normalized-<input>.wav.
Very simple:
./normalize.py -i <input-file> -v
The -v option turns on info messages. Check out ./normalize.py -h for more options.