db4o is an object database for Java and all .NET environments. Its features include ACID transactions, automatic class schema recognition, query-by-example, a S.O.D.A. object querying API, native queries, LINQ support on .NET, callback methods, memory files, cascade-on-delete, multi-threaded access, and Java Webstart and servlet support.
SPL is a powerful scripting language. It features hashes, regular expressions, objects, exceptions, a built-in template language, and has a C-style syntax. It can be used stand-alone or embedded in other applications. The entire SPL toolchain (compiler, assembler, virtual machine, etc.) is pretty small (about 100k on x86 architectures). One of the more advanced VM features is the capability to dump the entire VM state to a file and resume later. It even is possible to resume on another machine with a different architecture.
libubiqx is an in-memory database suitable for use in embedded systems. The libubiqx database management system is a fully functional DBMS API that supports both hierarchical and relational data architectures. It provides developers with robust and scalable data management tools for use in embedded systems or SNMP agent applications.
OpenCAN is a software platform for interacting with various Controller Area Network (CAN or CANbus) devices. It provides an abstract C++ interface that can be used to control CAN devices. Support for specific devices can be written as plugins, and then loaded through a simple API call. Each component is cross-platform, enabling the efficient development of CAN software on Windows, Linux, and Mac OS X.