Zyan Communication Framework simplifies development of distributed applications. It works on Windows, Linux, Mac OS, and Android platforms via .NET or Mono runtimes. It features LINQ support for three-tier applications, full duplex TCP support, traffic, compression, and encryption, transparent support for events and EBC (event-based components), and Windows and LDAP authentication support.
Nearforums is a lightweight powerful discussion forum that can be installed within minutes on Linux or Windows servers with MySQL or MS SQL database servers. It includes great features like sign-in with Facebook/Twitter, navigation with tags, full Web administration, built-in search engine, RSS feeds, and accessible HTML. It is SEO friendly.