TotalFinder is a plugin for Finder.app which adds tabs like those in Google Chrome, dual panels similar to TotalCommander, and other improvements.

ForkLift is a file transfer software, It allows you to transfer files using FTP, SFTP, FXP, WebDAV, Amazon S3 and even Bluetooth.

Unifyle connects Oracle Documents Cloud to all the different file storage silos including File shares, Sharepoint, FTP, BOX, Dropbox, Office365, Sharefile etc…

iFile is a complete file manager and viewer running under user root.

Otixo is an encryption and file manager for multiple clouds from one login.

EasyFind is an alternative tool to Spotlight, OS X's built-in search tool.