Grammatica is a C# and Java parser generator (compiler compiler). It improves upon simlar tools (like yacc and ANTLR) by creating well-commented and readable source code, by having automatic error recovery and detailed error messages, and by support for testing and debugging grammars without generating source code. It supports LL(k) grammars with an unlimited number of look-ahead tokens.
Libnet is a cross-platform library aimed at game developers. It has an abstract high level API, which encourages developers to make their games portable across platforms and network types
