I just bought a ¥5600 dealy from the local electronics district. It plays MP3, JPEG, MPEG4, WMV, and a mess of other formats off of USB keychain drives or SD flash media (which it navigates by directory, through a browser), and appears to ignore region coding on DVDs. I am as pleased as punch.
So far it doesn't like the .MP4 files that can be downloaded from Google Video, so I am not sure what's up with that. It's hard to dislike a machine that lets me play all the DVDs I own, and not just the ones from a given region. Golly, gosh, darn it, I fucking hate region coding.
Correction: It, and most units like it, appear to support WMA, not WMV. Audio, not video. Crapx0r!