My company has integrated with many platforms and systems. But when it comes to development we stick with Microsoft products. Our preferred development language is C# but we also use VB.NET in some circumstances. Our production applications contain one or more of the following technologies: ASP.NET Web Forms, ASP.NET MVC, Windows Services, Windows Forms, Windows Presentation Foundation. We try to stick with windows controls and tools as much as possible. The one rich third party tool set we really like to use is the Telerik control suite.
We have accumulated many re-usable components and interfaces. For example, say you want a cloud based internet application for internal employees only. And part of this application you would like to post training videos and monitor usage. This would all come out of the box with my base system. I have a private video channel on Vimeo where you can post videos through a web page and have them served to your employees.