For a project I was working on I needed to be able to upload multiple files via HTTP to a website.
You can put X Http FileUpload controls on your page but then you need to select the files one by one. So a busy job if you need to upload +100 files.
So I was looking on the web and found this great control on the code project from darick_c.
Here you have the URL: http://www.codeproject.com/KB/aspnet/FlashUpload.aspx
And attached the code and an example. I know you can download it from the code project site but you never know.
Have fun.
-Wesley