In Firefox, I view my site and get no warnings about insecure mixed content.
Using FireBug, I can see that every request is https.
In Chrome, I get the https crossed out in the address bar.
I viewed source in Chrome and then ran this regex /http(?!s)/ but the only things it found were the href attributes for some external links and the doc type and http-equiv meta tags.
Using Chrome's Resource Tracking revealed all requests were https too.
This includes Google Analytics, jQuery from Google's CDN and Facebook like scripts.
Is there any specific tool I can use to show non https requests, or anything further I can try?