Java applet allowing to upload files and folders.
BSEditor: JFileUpload - Java applet allowing to upload files and folders.
It comes with many add-ons:

JImageUpload allows previewing images before upload.
JImageFilter allows scaling images to save bandwidth.
JBatchUpload can queue and organize files to upload.
JDiskExplorer allows to browse, download files from remote folders.
JS3Upload targets Amazon Simple Storage Service upload.
JFileUpload products fit to many businesses involving web uploads.
Our customers are printing companies, video services, hosting
services, photographers, webmasters, CMS vendors, studios,
many industries, governments, universities and more. you can free download JFileUpload 2.5 now.