Meld is a visual diff and merge tool. It integrates with most version control systems. The diff viewer lets you edit files in place (diffs update dynamically), and a middle column shows detailed changes and allows merges. The margins show location of changes for easy browsing, and it also features a tabbed interface that allows you to open many diffs at once.
p4delta works with a project that is in the Perforce configuration management system. It lists the local files that have been added, changed, or deleted. Content differences are summarized, i.e., the number of lines of code that have been added, changed, and deleted. It can also add, edit, and remove the appropriate files to/from Perforce.
ded, the directory editor, allows you to navigate multiple file lists or a directory tree, viewing or changing file attributes rapidly. In addition to conventional file information, it operates on files' RCS or SCCS archives, making it useful for source control as well as system administration. It is curses-based.