Nice File Viewer is a software that presents the data stored in a computer file. it's used for exporting data in a different file format, or to copy information from the viewed to the system-wide clipboard.
QuickLook enables a very quick preview of file contents by pressing the spacebar. Supports different formats files such as music, videos, pdf, program code, etc.
Directory Opus is a file manager which allows you to viewing pictures, converting files, playing audio, opening Zip files, batch renaming and searching. It shows two folders in separate tree-view panes.
FreeCommander is a file manager for Windows with features of dual-panel technology, tabbed interface, Built-in archive handling, searching duplicates, simple FTP/SFTP client and so on.