This is another recipe-alike, self-reminder post. This one converts all FLAC files in a directory to MP3, which I do hardly now (because I have OGG-Vorbis support almost everywhere), but is still useful for some hardware players. Also, note that this properly saves ID3 tags and song length information (it took me some time to find about xingmux, which is in gst-plugins-ugly):

for i in *.flac ; do
  gst-launch-0.10 filesrc location="${i}" 
    ! flacdec ! audioconvert ! lame vbr=4 bitrate=224 
    ! xingmux ! id3mux ! filesink location="${i%.flac}.mp3"
done

Copy, paste, and you are done! ;)