Convert a bunch of AAC files to MP3 using ffmpeg and bash

Here's a little one-liner to convert a bunch of aac files to mp3 using bash and the non-free version of ffmpeg:

for i in *.aac; do ffmpeg -i $i -aq 2 `basename $i aac`mp3 ; done

A couple of things to note: the filename extension for aac is case-sensitive in bash. And this only works for the non-free version of ffmpeg that has AAC and MP3 enabled.