How to implement file upload progress bar on web?

Question

I would like display something more meaningful that animated gif while users upload file to my web application. What possibilities do I have?

Edit: I am using .

Answer 1

Some good .NET-specific help for doing progress bars can be found in Dino Esposito's MSDN Magazine articles from last July and August:

Context-Sensitive Feedback with AJAX (July '07)
Canceling Server Tasks with ASP.NET AJAX (August '07)