BTW a sidenote: contrary to what I said about MP4 Players, it seems like Microsoft MAY act very nervous under certain circumstances when you fiddle too much with their format. Nothings wrong with playing MP4-ASF Movies using the OS's functions, but when you start to offer ASF-Import function that would allow to rip ASF Content, you'll soon get unfriendly mails from billys army of lawyers. One case study may be VirtualDub, they had to remove ASF Support after Version 1.3c.