JDownloader is a popular download manager software for easy downloading of files from file hosting websites like Rapidshare, MegaUpload and so on. Now this cool download manager program is available in portable format. You can download the portable package, extract it and use it from anywhere (like USB drive).
Also See – 5 Best free Rapidshare Download manager
You can optionally use it with portableapps.com tool (as seen in above screenshot). It can also be used without portableapps.com tool, just extract and launch the downloader program. Portable version support basic functionality of multiple file downloading but there is no support to resume downloads. Download portable Jdownloader [63MB]