Is there a report that will show me who did not open the e-mail across n-campaigns?
You can use segmenting to create a list of people who have not opened specific campaign - see http://www.campaignmonitor.com/blog/archives/2007/02/creating_and_using_segments.html for help.
Regarding opens, you will also want to checkout http://www.campaignmonitor.com/blog/archives/2007/01/all_about_email_open_rates.html
So, if I create a segment that says Opened Campaign 1, or Campaign 2 thru to 8 (last one) and then deducted that list from the overall current subscribers that would give me the list of not opened at all people (subject to the many caveats re: open tracking) ?
Well you would just create a segment of 'did not open <campaign>' and get the list that way.