I bought a ZVOX www.zvoxaudio.com to hook up to my TV a couple of months ago and I'm pleased. I don't care much about home theater so I figured this might be a decent/cheap solution for movies; it works well. Not true stereo, but it does a good job of faking it. The drivers look like they are a quality product. I would think it might be suitable for a portable rig. I think it was designed for computers or Ipods.
-matt
-matt