I killed almost a year on a similar project and it flopped majestically.

I even worked out how to do the whole verification part that it works out of the box without the need for any software or 3rd party service. You just needed a Windows box. Still that made no difference whatsoever, because ultimately selling this sort of service is like selling insurance. You have to force people to think about bad things that could happen in order to make a sale, and that's just not everyone's cup 'o tea.

Postmortem - http://swapped.cc/certtime