JDiff is a tool which performs folder recursive comparisons and file comparison based on Myer's minimum set of differences algorithm. Based on this file comparison algorithm, it also provides a 3-way merge, which can run without a graphical interface. JDiff is released as an auto-executable jar file.
DiffKit is an application and a framework, for comparing two tables of data, field-by-field. The tables can come from any of a number of sources, such as an RDBMS or CSV file, and DiffKit is able to mix different kinds of sources in the same diff operation. It is like the Unix diff utility, but for tables instead of lines of text. Diffs can be reported at both the row and field level, and the user can configure what to compare, how to compare it, what to ignore). DiffKit is highly customizable with respect to the sources of tabular data, the details of the comparison, and the characteristics of the output (diff report).
This program is especially useful when the main difference between the two LaTeX files is in permutation of sections, moved equations, etc. Given 2 LaTeX files, it prepares 2 annotated LaTeX files showing which equations of the 1st file are identical, or close, or similar, to which equations of the 2nd file. It does the same with the pieces of text. It also saves the snippets of text and equations from each text into separate files in 2 new folders, allowing the user to see the difference using a diff program.
SafePatch lets you edit program files and track those changes creating "patches" which can later be reverted or reused in a different setup. It's written in PHP, but can patch non-PHP applications because no integration into their source code is required. A bundled Control Panel allows easy tracking, installing, reverting, and diffing of available patches. SafePatch has an intuitive text patch file syntax which is uniform for text and binary files and independent of the engine being patched, has default support for VQMod .xml patches and FluxBB README mods, is written in OOP and uses events (and thus is easily extensible), and doesn't need a database.