recorder@recorder:~$ ffmpeg -isync -f alsa -ac 1 -ab 128k -i pulse -acodec pcm_s16le -f x11grab -r 10 -s 1366x720 -i :0.0+0,0 -vcodec libx264 -threads 1 -crf 0 -preset ultrafast  output.mp4
ffmpeg version 0.8.1-4:0.8.1-0ubuntu1, Copyright (c) 2000-2011 the Libav developers
  built on Mar 22 2012 05:09:06 with gcc 4.6.3
This program is not developed anymore and is only provided for compatibility. Use avconv instead (see Changelog for the list of incompatible changes).
[alsa @ 0x14d38c0] capture with some ALSA plugins, especially dsnoop, may hang.
[alsa @ 0x14d38c0] Estimating duration from bitrate, this may be inaccurate
Input #0, alsa, from 'pulse':
  Duration: N/A, start: 1337016032.153355, bitrate: N/A
    Stream #0.0: Audio: pcm_s16le, 48000 Hz, 1 channels, s16, 768 kb/s
[x11grab @ 0x14f4520] device: :0.0+0,0 -> display: :0.0 x: 0 y: 0 width: 1366 height: 720
[x11grab @ 0x14f4520] shared memory extension  found
[x11grab @ 0x14f4520] Estimating duration from bitrate, this may be inaccurate
Input #1, x11grab, from ':0.0+0,0':
  Duration: N/A, start: 1337016032.257849, bitrate: 314726 kb/s
    Stream #1.0: Video: rawvideo, bgra, 1366x720, 314726 kb/s, 10 tbr, 1000k tbn, 10 tbc
Unrecognized option 'preset'
Failed to set value 'ultrafast' for option 'preset'