It's a web application that allow you to use Youtube offline. It's also a web application that runs on Google App Engine. With Google Gears future, it stores the flv file in you computer!! If you are interesting in this project also, welcome to download the code. I'll be glad to receive your feedback!!
Here is the web application on Google App Engine:
Thanks to your feedback. Here are my email and blog: Email : email@example.com Blog : http://blog.coolyuonline.com/