QuantLib is a cross-platform, quantitative finance C++ library for modeling, pricing, trading, and risk management in real-life. It is also wrapped as Python/Ruby/Scheme modules. Extensions for Excel, R, and Mathematica are available. Other such extensions are under consideration. QuantLib offers tools that are useful both for practical implementation and for advanced modeling. It features market conventions, yield curve models, solvers, PDEs, Monte Carlo (low-discrepancy included), exotic options, VAR, and so on.
Peers is a distributed programming toolkit designed for building peer-to-peer systems. The toolkit is a hybrid language project which offers low level primitives for managing concurrency and communication. Using these primitives, complex P2P protocols and complete systems can be designed and implemented in Python, while maintaining high performance for critical operations.