How to show a warning or bar from BHO in Internet Explorer?

Question

I'd like to display a warning on some websites, similar to the warning IE shows when it blocks an ActiveX.

Or a bar (not a tool bar) like Google Translate (from the Google Toolbar):

I'm trying to do this in C# in a Browser Helper Object. Any code sample, or reference on the subject?

UPDATE: this question explains how to do it in C++, but I cannot figure out how to translate this into C#

Answer 1

The Information Band (and it's successor notification UI) is not extensible. Faking it is also frowned upon. You could inject JS+HTML into the page to mimic it, however.