I recently had a thought about the way many modern browsers display information about a site's security certificates. At least Firefox shows a very noticeable blue box in the address bar on sites that have valid SSL certificates, and practically all browsers give an even more visual cue on sites with more expensive EV SSL certificates.
My theory is that a company can force SSL on their website to subconsciously appear more trustworthy, even though the certificate has nothing to do with the credibility of the company itself. Is there any research to either back or refute this? If not, are there any examples of a company website that is available through both HTTP and HTTPS?