Is Google Chrome embeddable?
Google Chrome is basically WebKit layout engine + nice UI. And WebKit can be embedded.
There's also chromium embedded framework (CEF).
And finally, check out Awesomium.
Update 2:A very good fit for this would be the new Electron Shell
Update:As a commenter points out under this answer, this is no longer supported. For good reasons I guess.
Recently Google released the Chrome Frame active X for MS IEsee if that helps
I've just release a pre-alpha version of CefSharp my .Net bindings for the Chromium Embedded Framework.
Check out source or grab bins and give me your thoughts: https://github.com/chillitom/CefSharp