Just a thought, but would it work...what if you created a signature used the anchor text you required, hyperlinked it to your website then made the colour white against a white background so it hides. Yes I know it will leave a blue line underneath - but would it work? Providing were you left the link is do follow.
I would be interested to know if this would work from some people as well. I would say you would have to be careful with you coding. Such as the background must be an image instead of the background coding being white and the link color being white.
Hello, Hiding any content (other than drop down menus and stuff, which make sense to be hidden) is considered cloaking and would get the website that the link is on penalized thus making the link worthless.
It would probably work, but it would affect your reputation and people may look at you as a spammer for hiding code.