IntegraStudio is a pioneering solution allowing to develop true Java software under Microsoft Visual Studio.

IntegraStudio interfaces with standard JDK and existing Java implementations. With IntegraStudio you can develop real world Java applications, just as with other industrial-strength Java development environments.
Free beta
WinGDB is an extension for Visual Studio allowing to develop programs with GNU tools.

WinGDB works with remote Linux/Unix systems. It supports edition, build, deployment and debugging.

Possible development targets supported by WinGDB include: remote Linux/Unix desktop machines, embedded Linux systems, embedded bare-metal devices, Windows applications developed with MinGW or Cygwin.
VSScript is a macro interpreter for Visual Studio, using popular Lua scripting engine. It support most of the macro APIs (DTE) provided by Visual Studio. VSScript can replace Macros functionality removed from Visual Studio since VS 2012.

VSScript macro editor supports IntelliSense and debugging of macros.