Large browser based file uploads via HTTP can be cumbersome. Recently I had to find an alternative to a Java based uploader. SwfUpload combines Flash & JavaScript and is highly degradable. It places a 1x1px Flash application in the page and then the actual interface is CSS and JavaScript (which polls the Flash app).

One great feature is that if Flash is not installed or JavaScript is disabled/limited the solution uses CSS to display a degraded version - try using a standard upload control here.

www.swfupload.com

http://swfupload.org/project/asp_net