After several hours of working on this, I came up with an ideal set of commands to encode video clips for playback on a Treo 600.

This REQUIRES MMPlayer on your Treo and Mencoder on your Mac. This will not work on Kinoma.

Your source file can be .vob files, .mpg, .avi, and select windows media and/or real. Basically any format supported by Mplayer.

What this will do is re-encode your video and be somewhat optimized for your Treo. I am still working on a few things for this, including a GUI front end for OS X.

The results are awesome... (considering I can watch movies like Orange County on my CELL PHONE)

1) Launch the terminal. Copy and paste this in the terminal windows:

for 4:3 video:

mencoder -srate 24000 -oac mp3lame -lameopts br=32:cbr:vol=6:mode=3 -ovc lavc -lavcopts vcodec=mpeg4:vhq:vbitrate=64:keyint=300 -vop scale=160:120 /path/to/input.file -o /path/to/output.avi
for 16:9 video:

mencoder -srate 24000 -oac mp3lame -lameopts br=32:cbr:vol=6:mode=3 -ovc lavc -lavcopts vcodec=mpeg4:vhq:vbitrate=64:keyint=300 -vop scale=160:96 /path/to/input.file -o /path/to/output.avi
This should encode faster than realtime for you.

I will post updates for this as needed. Hope this helps some Treo/Mac owners.