Hacker groups Anonymous and LulzSec are calling for a boycott of PayPal, following the prosecution of 14 people for allegedly carrying out DDoS attacks against the online payment company last year.
The attacks were carried out in retaliation for the fact that PayPal was refusing to process payments to WikiLeaks - which it is still continuing to do.
"In recent weeks, we've found ourselves outraged at the FBI's willingness to arrest and threaten those who are involved in ethical, modern cyber operations. Anonymous 'suspects' may face a fine of up to 500,000 USD with the addition of 15 years' jailtime, all for taking part in a historical activist movement," say the groups.
"Many of the already-apprehended Anons are being charged with taking part in DDoS attacks against corrupt and greedy organizations, such as PayPal."
Unusually, though, the groups are calling for an entirely legal form of protest. They want supporters to close their PayPal accounts immediately and publicise the cause.
"Tweet pictures of your account closure, tell us on IRC, spread the word," they say. "PayPal's willingness to fold to legislation should be proof enough that they don't deserve the customers they get. They do not deserve your business, and they do not deserve your respect."
Anonymous says the campaign is working already - withn ten minutes, it claims, 50 people were in the process of canceling their accounts. Many, they say, are donating any remaining funds to charity.
If the pace keeps up, they say, some 9,000 people could have followed suit by the end of the week.