Chicken is a Scheme compiler that translates most of R5RS Scheme into relatively portable C. It supports fully general tail-call recursion, first-class continuations, and has a very flexible and efficient interface to C and C++. Chicken implements several extensions to the Scheme language: lightweight threads, pattern matching macros, dynamic loading of compiled code, and various object-oriented paradigms, such as TinyCLOS, and others. The library system includes hundreds of convenient modules for practical use.
Pike is an interpreted, object-oriented, dynamic programming language with a syntax similar to C. It includes a powerful modules system that, for instance, has image manipulation, database connectivity and advanced cryptography. It is simple to learn, does not require long compilation passes and has powerful built-in data types allowing simple and fast data manipulation.
J2ObjC is a tool from Google that translates Java code to Objective-C for the iOS platform. It enables Java code to be part of an iOS build, as no editing of the generated files is necessary. The goal is to write an app's non-UI code (such as data access or application logic) in Java, which can then be shared by Web apps using GWT, Android apps, and iOS apps. J2ObjC supports most Java language and runtime features required by client-side application developers, including exceptions, inner and anonymous classes, generic types, threads, and reflection. JUnit test translation and execution are also supported.
Steel Bank Common Lisp is a development environment for Common Lisp, with excellent support for the ANSI standard: garbage collection, lexical closures, powerful macros, strong dynamic typing, incremental compilation, and the famous Common Lisp Object System (multimethods and all). It also includes many extensions, such as native threads, socket support, a statistical profiler, programmable streams, and more. These are all available through an integrated, interactive native compiler which feels like an interpreter. SBCL is unique in being a multiplatform native compiler which bootstraps itself completely from source, using a C compiler and any other ANSI Common Lisp implementation.
Octave is a high-level language, primarily intended for numerical computations. It provides a convenient command line interface for solving linear and nonlinear problems numerically, and for performing other numerical experiments. It may also be used as a batch-oriented language.
crosstool-NG is a versatile toolchain generator, aiming at being highly configurable. It supports multiple target architectures, different components (glibc/uClibc...) and versions. crosstool-NG also features debugging utilities (DUMA, strace...) and generation tools (sstrip...).