Plupload allows you to upload files using HTML5 Gears, Silverlight, Flash, BrowserPlus or normal forms, providing some unique features such as upload progress, image resizing and chunked uploads.
The developers of TinyMCE brings you Plupload, a highly usable upload handler for your Content Management Systems or similar. Plupload is currently separated into a Core API and a jQuery upload queue widget this enables you to either use it out of the box or write your own custom implementation.