What is it?
A ‘flash mob' is a sudden gathering of like-minded people in a public place who are usually summoned by text or email. They perform an unusual act, then disperse.
This one, held on 18 October at the O2 Centre, a shopping mall in north London, attracted more than 60 of World Jewish Relief's volunteers and supporters, who assembled to donate winter clothing and create a human logo for its Operation Winter Survival campaign.
The charity wanted to fill 3,000 bags before its deadline of 8 November, and the flash mob's aim was to encourage others to do so.
Why a flash mob?
To promote the campaign with a unique and unexpected event in which people of all ages could take part. Also to encourage website traffic and participation in online activity behind the campaign.
"The flash mob created a buzz and brought the campaign back to the forefront of people's minds for a final push before our deadline," says Paul Stein, the charity's head of fundraising and communications.
How much did it cost?
Nothing at all. The O2 hosted the event free of charge, and volunteers documented the day with photography and video.
How was it promoted?
The marketing campaign was purely viral. The charity sent emails with instructions and maps to all supporters on its database. Those people were encouraged to forward the message to their contacts.
What were the results?
Stein says the flash mob was a success.
"To date the YouTube clip has received more than 437 views, the campaign has raised more than £3,000 and we have had nearly 600 sign-ups to donate so far, with more than 50 organisations on board."
Third Sector's verdict
An imaginative way to engage supporters of all ages and to elicit donations.