Thousands of people switched their accounts from banks to credit unions on Saturday as part of the Facebook-organised Bank Transfer Day.
The Facebook event was set up by Kristen Christian, a 27-year-old art gallery owner from Los Angeles, in response to Bank of America's plan to introduce a monthly $5 debit card fee - a move since abandoned.
Christian's call for people to ditch big lenders in favour of non-profit credit unions on 5 November quickly gathered momentum through Facebook, Twitter and the mainstream media.
By Saturday, boosted by association with, and support from, the separate Occupy Wall Street movement, the Facebook event page had received over 80,000 'RSVPs' while a new Bank Transfer Day Facebook page has received over 59,000 'likes'.
According to the Wall Street Journal, on Saturday Seattle's Boeing Employees' Credit Union signed up a one-day record 659 new members while at the opening of a Randolph-Brooks Federal Credit Union branch in Pflugerville, Texas, "the parking lot was so full that customers had to leave their cars across the street".
Credit Unions have embraced the movement, claiming that since 29 September, when BofA unveiled its debit card fee plan, they have welcomed at least 650,000 new members.