SANSA user's guide (mp3 player from SanDisk)
VoIP Voice over IP

arecord -f CD | aplay records from your mike and plays it back after a very short delay

lame input.wav output.mp3 converts 'wav' file to 'mp3' file

id3tag change mp3 tags

mplayer infile.wma/ra -ao pcm input.wma -ao pcm:file=output.mp3 converts 'wma' to 'mp3'