Rhino 3D Users Contact list data sale Spam?

I received an email the other day which I found a bit odd, has anybody else received this or does anybody know where this is coming from?

Not without the unabridged source of the e-mail (that is all headers etc in raw text form). And even then probably guesswork at best.

This is a common spam. I get one of these offering the users of almost every CAD/CAM/CAE about once per month.

Right. So I guess the best is just to mark it as spam and move on.