Teanntas, are there any circumstances in which you personally would be willing to inject yourself with an infective dose of HIV, as Robert Willner did? I can answer that definitively for myself - I wouldn't, because my best guess at the moment is that medical science is right about the connection between HIV and developing Aids and it's not a chance I'd ever see the point of taking.
There are people who have taken seemingly absurd risks in the name of medical science - for example, a medical scientist in Australia gave himself ulcers by drinking a glass of H. pylori bacilli in water, and I even believe someone was brave (or stupid?) enough to drink a glass of cholera bacilli.
[EDIT: this is indeed true;]
"In this Sutherland was simply following the orthodox belief of his time. His near contemporary Max von Pettenkofer (1818– 1901) the German public health campaigner, was convinced that germ-bearing cholera excrement would merely prompt a process whereby ‘a specific cholera-miasma is developed, which is then spread along with other exhalations into the houses’. In the words of the Dictionary of Scientific Biography ‘Pettenkofer readily accepted this vibrio [cholerae] as his “x” factor but refused to modify his views on the paramountcy of the telluric “y” factor’ as the cause of epidemic cholera. So confident was Pettenkofer that cholera germs alone were harmless that in 1892, during a virulent epidemic in Hamburg, he publicly swallowed water which contained cholera bacteria. He suffered diarrhoea and excreted samples of the Vibrio cholerae for several days but suffered no worse effects, probably because he had developed immunity from an earlier, mild infection. This demonstration was seen by his followers as a vindication of his theory, thus briefly setting back the cause of medical science."
http://ije.oxfordjournals.org/content/31/5/912.full
A virus such as HIV, though, can't be treated with antibiotics and so you're stuck with it unless your immune system can defeat it - which, despite what that guy was saying in the video you just posted, is far from guaranteed.