I really hope this takes off, there have been several efforts to bring PKS & PKE to the browser than have unfortunately just withered & died.

WebPG (http://webpg.org/) is the best implementation so far for GMail integration, and as far as I can tell it's the only one still being developed, but it falls over at the last hurdle, it won't send the email :)

As a resident of the UK, with our governments boner for introducing a snoopers charter this kind of thing really interests me.