Feel free to add your own SpiderMonkey-based open source projects (and if necessary add categories)!
- Cocos2d-JS - Cocos2d-JS is a cross-platform Game Engine which embeds SpiderMonkey, providing the same API for both web and native platforms. Getting started here.
- Flusspferd - (newer) C++ bindings
- libjspp - C++ template based library for extending & embedding SpiderMonkey; works with SpiderMonkey 1.8.5 and above, has lots of goodies
- Spiderape - the oldest C++ bindings for SpiderMonkey
- http://alain.frisch.fr/soft.html#spider - bindings to embed SpiderMonkey in OCaml applications
- jsapigen - generates bindings for embedding SpiderMonkey in C applications
http://www.jsdb.org/ - a JS Shell with native objects for files, networks, databases, compression, email, etc.
http://code.google.com/p/gpsee/ - commonJS platform, native-language module interoperability methods, modules, etc. for SpiderMonkey. Designed to supplement existing embeddings, GPSEE ships with a sample trivial embedding, a scripting host, and an augmented version of Mozilla's JS Shell. Bundled modules include support for ByteArray, ByteString, CGI, POSIX Signals, FFI, and more.