Save the Children will be encouraging members of the public to stick plasters bearing the word 'ouch' in all manner of unusual locations from next Tuesday.
The aim of the Ouch campaign is to create a visual petition to raise awareness of the plight of the 250,000 African children who have died in the past year because their parents can't afford to pay for healthcare.
Save the Children claims this is the first mass-market charity campaign to use multimedia messaging services: pictures and videos sent by mobile phone.
The charity will be giving away 100,000 postcards with removable 'Ouch' plasters in Metro at 10 London mainline railway stations. The message on each postcard will ask 'Where will you stick yours?'
Save the Children is hoping that people will use their imaginations to stick them in different venues, then use MMS to take pictures and text them to a special number. All the pictures will then be uploaded onto the charity's website, which will be used to highlight the issue to the world. Larger versions of the images will be projected onto key buildings in the capital.
The postcards will continue to be available in Save the Children shops and selected publications for another few weeks. The launch of the campaign will coincide with the publication of a report called Paying With Their Lives: the Cost of Illness for Children in Africa.
"We are using this visual petition to renew pressure on the Government," said Joe Barrell, head of communications at Save the Children. "The Ouch concept might seem gimmicky, but there's a very serious issue at stake.
"In Africa children are dying because their parents can't afford a doctor.
Simple medicines that we take for granted cost the equivalent of a month's salary in Africa. It would cost a tiny fraction of the money that was committed at the G8 summit to resolve the issue."
Save the Children also hopes to use texting and MMS as a supporter recruitment mechanism.
Barrell added: "We will be looking at ways of using the texts to convert people into more active supporters."