Diluculum is a library that intends to make the coexistence of C++ and Lua more harmonious. In this regard, it offers essentially three "services": a nice way to access data stored in a Lua interpreter; a not so bad way to write functions in C++ and make them available to Lua; and a limited and just barely usable way to register C++ classes and objects in a Lua state.
SQBind is a pretty simple, yet powerful binding library for the Squirrel language. It includes support for binding classes, methods, static methods, member variables, functions, enums, and C types. It can either manage pointers or leave them unmanaged. It also recognizes functions that receive pointers or references and passes values accordingly. It also easily lets you use your own types for taking care of native Squirrel types, such as your own (or std::) string class, table class, array class, etc.