https://addons.mozilla.org/en-US/firefox/addon/desopa/
or
[add-ons mozilla base URL ] (slash) en-US (slash) firefox (slash) addon (slash) desopa (slash optional)
in case it is filtered.
Disclaimer: I developed it
Some might argue that speech telling you how to commit a crime is not protected speech, but the Anarchist Cookbook is legal to possess as well.
Dammit Jim, I'm a hacker, not a lawyer. This is not legal advice.
You have to remember, for a lot of people their online experience ends at facebook, youtube and hotmail. Sites like reddit, stack overflow, digg, all have audiences that generally don't use IE and will also be able to find a way around a SOPA block. Sure, these sites will lose a lot of traffic, but SOPA will FAR from kill them.
Or something to that effect.
They'll have fun moderating every scrap of user generated content they want to make use of or shut all their forums down, and still, circumvention tools will be everywhere.
If this passes, not only will they find people will create tons of tools to make circumvention easier than ever, but darknet efforts redoubled and work to make the net in general more censorship resistant explode; and people doing their worst to ensure it'll be harder than ever to stop piracy.
And with that other bill, where the US can arrest anyone, anywhere, anytime, it's not good enough to not be American.
"[T]his version targets software developers and distributors as well. It allows the Attorney General (doing Hollywood or trademark holders' bidding) to go after more or less anyone who provides or offers a product or service that could be used to get around DNS blacklisting orders."
Second paragraph: https://www.eff.org/deeplinks/2011/11/hollywood-new-war-on-s...
(Disclosure: I'm a developer on addons.mozilla.org; EDIT: Changed the post to add a source)