Ninject runs on a variety of .NET platforms:
- .NET Framework 2.0, 3.0 and 3.5
- .NET Compact Framework 2.0 and 3.5 (Ninject.Core and Ninject.Conditions)
- Silverlight 2.0 beta 2 (Ninject.Core, Ninject.Conditions, and all shipping extensions)
There are a few competing dependency injection frameworks available but this on seems to have a lot to offer and a strong following of developers using it. Nate even has some swag, in case you might be looking for a shirt to help support his project.