Well you could use the HTTPS Everywhere Firefox plugin by the Electronic Frontier Foundation.
If you don’t want your employer viewing your Google search, or Twitter, it might work for you.
The 0.2.2 release of HTTPS Everywhere currently has support for the following 27 web sites:
Amazon, DuckDuckGo, EFF, Facebook, GMX, Google, GoogleAPIs, GoogleServices, Identica, Ixquick, Live, Mail.com, Meebo, Microsoft, Mozilla, Nederland, NYTimes, PayPal, Scroogle, Torproject, Twitter, WashingtonPost, Wikipedia, WordPress, zGentooBugzilla, zNoisebridge, Zoho
You can download the HTTPS Everywhere plugin here.