Does anyone know how to do this without using a third party transcoder? My laptop is a normal Vista build, not a Windows Media Centre.

The 360 can decode and play divx itself. All you need to do is put the movie on a memory stick and plug it in the xbox usb slot. It will run off an external hard drive too.

You can stream it over wireless if your 360 has an adaptor, but its slightly more complicated to set up and a little slower to fast forward etc due to the obvious band width restrictions of wireless.

The only thing the 360 cant play is some of the larger MKV files.

I think if you've got the newer interface installed (with the wii me kinda fella) then it'll play some formats as standard, but if it can't it'll use the XBOX live service to download the relevant codec (if you're online and a silver/gold member). I've got mine playing most things now, not MKV files though which is a pain.

I just create a share on my PC where I store my videos and allow the XBox access to it. Streams over my (wired) network and all is good. Even capable of doing HD as well

Thanks chaps