Vixy.net is the absolute best way to capture and convert YouTube and other viral videos for your portable media player. And...if you have a sub-$100 economical Zvue media player, the .avi conversion option will allow you to play the videos without any additional conversion steps.

Vixy allows you convert a Flash Video / FLV file (YouTube's videos,etc) to MPEG4 (AVI/MOV/MP4/MP3/3GP) file online. It is using a compressed domain transcoder technology. It converts FLV to MPEG4 faster and less lossy than a typical transcoder.

When you submit an url, it will download and convert to the video format. Then you can download the converted file.