With Gift Aid, your generous donation of £10 would be worth £12.50 at no extra cost to you.
I am a UK taxpayer and I understand that if I pay less Income and /or Capital Gains Tax than the amount of Gift Aid claimed on all my donations in the relevant tax year, it is my responsibility to pay any difference.
In our 35th year we’re asking people to donate £35 – that’s just £1 for every year we’ve been providing life-changing information. Any donation you make helps us continue our work towards a world where HIV is no longer a threat to health or happiness.
First-hand accounts of living with HIV; qualitative research on HIV prevention and treatment issues; and profiles of leading figures in HIV activism and science.
The Guardian
POZ 
CNN
Time
Slate
The New Yorker
New York Times
TheBody
PinkNews
NBC News
Prepster
TheBodyPro
UNAIDS
BBC News
The Lancet (free registration required)