JUpload is a component which can be embedded into existing websites for incredibly simple upload of multiple files. It also supports recursive adding of folders Drag&Drop, provides a lot of features for image processing prior to the upload and has tons of customization options.
It is more comfortable and easier to use than any browser's internal file selection dialog. The user can easily manage the structure of files and folders to be uploaded and a status monitor shows information about what is currently happening in Details. Features include Image Preview, thumbnail creation, upload resuming, secure transfer, image resizing, context-menus, file size checking, complete JavaScript support, plugins and much much more - have a look at the Features page!
And if you don't like a feature: Simply customize, deactivate or Replace It with your own implementation in Javascript, Java or other languages supported by your browser.