UPXcmdis a freeware GUI (Graphical User Interface) for excellent executable packer, UPX (Ultimate Packer for eXecutables, upx.sf.net).
UPXcmd package contains a new program, UPXcmd DropBox. Dropbox allows you to compress your files by dragging them to an always on top window. DropBox uses UPXcmd main program’s settings for processing.
Download: UPXcmd 1.3