Firefox
For me, the best solution would be to include Tor in Firefox's Private Browsing Window. This would bring millions of Tor users and would be a serious boon for Firefox itself, which has been languishing in terms of PR. They actually had plans for this, but for some shady reason they decided not to go ahead with it. I suspect LEA and government asked them to shelve the idea, for this would make tracking people's internet movements a lot more difficult. And oh, think of the children!