Hacktivist group Anonymous tweeted at Anon_central, "Stop the E-PARASITE Act," before linking to a campaign at the 'We the People' organisation's web site.
There SOPA is called a pathway to the "Great Firewall of America" in a barb that draws a comparison between the US and the glorious People's Republic of China.
"This Bill would allow essentially allow A Great Firewall of America and would be a shameful desecration of free speech and any sort of reasonable copyright law," says the introduction to the petition.
"It would also put pressure on ISP companies to monitor their users like never before, a gross invasion of privacy. This bill is a direct assault on a free internet and a shameful attempt by copyright lobbyists to destroy net neutrality. Essentially it's a censorship law that would end the internet as we know it in America."
The petition has been signed over 41,000 times. Another online campaign with more support is a page at Tumblr that directs opposition calls to US legislators. Last week, the EFF revealed that it is generating 3.6 calls per second to the US Congress in opposition to SOPA.
"Free speech takes a beating" was the heading on a blog from the American Civil Liberties Union (ACLU) the day after the House Judiciary Committee's hearing on SOPA last week. The hearing witnesses were heavily waited in favour of supporters, wrote the ACLU, and was swift and precise in its intentions.
"Six witnesses were slated to testify and only one, Katherine Oyama, policy counsel for Google, was there to testify against the bill," it said. "The packed hearing lasted just over three hours, and most of that time was spent ganging up on Google and other opponents of the bill, with many members of the committee claiming that critics' concerns over the bill are unfounded."
Only one witness voiced opposition to SOPA as it stands, and she was browbeaten and bullied. "When members of the committee were given a chance to question the witnesses, the questions were few and far between for those who spoke out in support of SOPA," it added.
"This left only one witness to take the brunt of interrogation. Despite the fact that several of the witnesses pointed out parts of the bill that needed work, [Katherine] Oyama, policy counsel for Google, was left to point out the critical flaws with the legislation. Like other critics of the bill, Google believes that the scope of the bill is too broad and the threat that it poses to law-abiding citizens' freedom of speech is one we simply cannot ignore."
Closer to home, Loz Kaye, the leader of the UK Pirate Party, warned that SOPA would not only affect the internet as Americans know it, but the internet as a whole.
"SOPA is an attack on the very heart of how the Internet functions. Such sweeping draconian legislation threatens any kind of share-content site on the web. It should give sponsors of the bill pause for thought that even such major companies as Google, Yahoo and Facebook have been vocal in their opposition," he said in a statement to the INQUIRER.
"This bill affects us all with the threat to seize foreign domains. It is frankly typical of the arrogance of the US to think we should all be subject their authority. The European Parliament has rightly criticised this outrageous suggestion. If American law makers are determined to go down this route, then Europe should show that we will stand up for the future of the Internet."