About 9 months ago I posted about HTTPS Everywhere | Electronic Frontier Foundation hoping someone would port the HTTPS Everywhere extension for Firefox to force HTTPS in other browsers like Google Chrome, Microsoft Internet Explorer et cetera.
In the mean time, I found out about HSTS (HTTP Strict Transport Security), which is supported by FireFox 4, and Chrome 12.
Also in the mean time I found about a few HTTPS enforcer extensions for other browsers.
For instance, there are two similar Google Chrome Extensions to HTTPS Everywhere:
Internet Explorer does not have such an extension.
Opera has the Security Enhancer extension.
Next to HTTPS Everywhere, there are the ForceHTTPS and NoScript extension for FireFox (NoScript also supports HSTS).
FireFox 4 supports HSTS out of the box.
So now you have a choice!
–jeroen