Just studied settings for avidemux2, winff and x264. And did this
http://www.megaupload.com/?d=3026ZNIN
It's The dark knight trailer 2 optimized for N900. But i´m not really sure if it´s smooth because bitrate hits sometimes quite high.

Workflow was following:
- Download 1080p trailer from apple page with wget (useragent quicktime)
- Extracted audio with winff (made ac3 192 and surround, so yeah little loss here)
- Avidemux trial and error with video x264 settings until succeeded
-- Mplayer resize (bilinear, lanzcos3 made weird horizontal lines which could be seen on black scenes) 800x336
-- Msharpen (because when ever you resize down it´s good to give little sharpen to picture to make things look crisp)

- Audio from external ac3 to aac 160 kbit stereo. Had to put gain automatic -3db because audio was clipping on explosions.

I´m pretty satisfied with result, but please make your judgments and comment.

ps.
Everything would been much easier if handbrake could downmix multichannel aac files properly. But on the other hand i like to put sharpen filter and thats not so easy in handbrake.

.edit
Sounds like that audio is weird. Next time I try use audacity to mix surround to stereo properly. Now it sounds like speaks are on right channel.