Marcus Tander - aka Mediaadonis - has discovered a way to check if your site has been penalized or banned in Google. How long this flaw in the system will remain open one cannot tell, but it is working right now.
All you have to do is add hyves as a subdomain to the front of your domain. Hyves.yourdomain.com would be what you put into the browser and look at the page rank - through a PR toolbar for the page that comes back. It will be an error page that normally does not show any rank.
So if you are getting a PR 7 all is right with the world. If you get a PR 4 there is a penalty involved and if it is PR 0 well you have been banned.
Sorry for the lack of clarity of the earlier edition of the story. Thanks Marcus I am just an idiot sometimes - had the toolbar turned off and was expected some miracle page to be generated. Goes to show what happens when you ignore PR.