I don't think this will survive a multi-billion dollar lawsuit.
This is easily circumvented with modern CSS though. Just put your image as the background and overlay it with text or a block link. You can do it with no visual changes to the end users. You can even do image based rollovers by changing the background.
Sure if you don't mind breaking browsers with no CSS support (yes I love throwing the monkey wrench....>)).
I think I'll just continue to link to whatever I damn well please.