Ding is a dictionary lookup program for the X Window system on Linux/Unix. It comes with a German-English Dictionary with about 253,000 entries. It is based on Tk version >= 8.3 and uses the agrep or egrep tools for searching. In addition ding can also search in English dictionaries using dict(1) and check spelling using ispell(1). It has many configuration options, such as search preferences, interface language (English or German), and colors. It has history and help functions and comes with useful key and mouse bindings for quick and easy lookups.
LanguageTool is a style and grammar checker that currently supports English, Polish, German, French, Dutch, and other languages to a different degree. It scans the words and their part-of-speech tags for occurrences of error patterns, which are defined in an XML file. More powerful error rules can be written in Java.
Ctalk adds classes, methods, operator overloading, inheritance, and complex object expressions to otherwise standard C programs. Programs can use only a few Ctalk objects and methods in an otherwise standard C program, but the language can be used to write entire programs also. Ctalk works on most if not all of the systems that support GCC, the GNU C compiler. The package includes the language, class and run-time libraries, example programs, tutorial, and language reference.