I'm currently learning OpenGL. I'm a .NET programmer and I'm wondering if there's a good toolkit, API, add on, or other for building GUIs in OpenGL that will work well with .NET without massive effort?

Any suggestions or advice would be helpful.

I've used an OpenTK control within Winforms successfully, and it's pretty easy: http://www.opentk.com/doc/chapter/2/glcontrol

Unless you mean creating a custom GUI inside OpenGL, in which case I don't have much experience.

I've used an OpenTK control within Winforms successfully, and it's pretty easy: http://www.opentk.com/doc/chapter/2/glcontrol

Unless you mean creating a custom GUI inside OpenGL, in which case I don't have much experience.

Yeah I was talking about creating GUI's inside an OpenGL graphics space. But now that I think about it, hosting the OpenGL control inside a WPF GUI might be enough.