jDownloader: is open source, platform independent and written completely in Java. It simplifies downloading files from One-Click-Hosters like Rapidshare.com or Megaupload.com - not only for users with a premium account but also for users who don't pay. It offers downloading in multiple paralell streams, captcha recognition, automatical file extraction and much more. Of course, JDownloader is absolutely free of charge.
Hotfile: Allows users to upload and download files with any web browser. Non-registered users are allowed to upload up to 400 MB at once. After a successful file upload, the user is given a unique URL which allows others to download the file. Non-registered users have to wait 15 seconds in the download queue.
FileServe: FileServe's file sharing service lets you upload movies, upload music, store documents, images, presentations, zip files and much more. Any file in any file format can be uploaded for free to FileServe. The file size supported for each file you upload can be up to 2 GB. There is no limit to how many files you can upload and how many times each file can be downloaded.