When Rhys Morgan was 15 years old and diagnosed with the painful condition Crohn's Disease, he logged on to a support forum - where he discovered that a very dangerous "miracle" cure was being peddled.
After doing some research, he discovered that forum members were being actively encouraged to drink "Miracle Mineral Solution" which turned out to be a solution of bleach, and to continue with this treatment even when they suffered resulting symptoms such as burning. Upon challenging its promoters, Rhys was banned from the forum.
You can read how that went here at "Bleachgate", and take a look at this list of links to see the results of Rhys's determination to get more knowledge out there. It went as far as to be banned in Kenya, and Rhys got on the BBC (twice), Wales Online, and won the James Randi 2010 award for "Grassroots Activism".
Since then, he has also written about the Burzynski Clinic in the US, which claims to treat cancer with "antineoplaston therapy". This resulted in a representative issuing libel threats and, upon learning that Rhys was a teenager, threatening to inform his school and sending him an image of his house. Similar threats were made to other UK bloggers (highlighting the need for libel reform in the UK), but none have yet been followed through. Rhys asks here in the Guardian why the Burzynski Clinic is unwilling to simply publish its methodology and results, rather than threatening its critics.
Rhys, now 17 (though he'll be 18 when he does the talk), plans to continue his campaigns against unproven and dangerous "miracle cures", and will be talking to us about both these episodes as well as a history of the "miracle cure". You can also catch up with him on his blog and follow him on Twitter at @rhysmorgan.