While going through my logs I noticed that I have about IP address a day that crawls my site at a rapid pace and doesn't follow robots.txt and doesn't expose itself as a SE spider. My assumption is that these are site scrapers or other people taking up my bandwidth. What I want to do is create a honeypot and ban these IPs for a set amount of time. Here is my idea of how to create this.
On each page I will have a 1 pixel image that has a link going to a ban user page. On this page I will store the users IP address in a database and anytime that the IP address tries to access my site for a 7 day period will receive a message saying that they have been banned. Since my site is completely dynamic I can do this relatively easily. By using a 1 pixel image it should prevent normal users from clicking it. Also I would put nofollow in the tag so legitimate SE spiders should not visit that page.
My question is will Google think that the 1 pixel image is black hat and penalize me? Also are there any other pitfalls that I might not be thinking of?