Start a blog.
I'm not kidding.
Why?
Well, for a moment, let's leave out the reasoning of your argument and think about the method.
If I call you or email you and begin to pitch my idea, you are being interrupted. I am forcing you to react in real-time. It's an intrusion, either way, into your life.
If, however, I just put my thoughts out on a blog and you voluntarily go there, the nature of the conversation has already changed.
Now, you are, potentially, more open to my ideas.
You don't have to agree, that's fine, but because you are willingly putting yourself into the dialogue and thoughtstream, the conversation is likely to be more productive.
We've all been in conversations where the manner of presentation destroyed the content.
And, don't worry about numbers, worry that the "right" people are reading it (be it internal or external).
A quick example...
I have a friend who is a lawyer in DC working in pharmaceutical regulatory issues. He's a big reader of this blog and he decided that he could be a blogger.
He's got 300 readers a month, not huge, but you know what? It's the right 300 people. He's viewed as an expert in his industry and that helps him build out his business.
See Seth's post (a slightly different take) on an internal blog.