Check this out: Circumcision and HIV Risk

Two theories how circumcision can lower HIV risk:
Circumcision Changes Penis Bacteria Ecosystem, May Explain Lower HIV Risk

Fact or Fiction?: Circumcision Helps Prevent HIV Infection

Check this out: South African Guy Chooses to Undergo Xhosa Circumcision

A South African guy joins his black friends and gets circumcised in the traditional Xhosa way:
Circumcised with no anaesthetic.

For the Xhosa traditional ritual circumcision is an essential part of becoming a man and anyone who refuses to undergo the procedure will not be treated as an adult.
Sometimes they let people who are not actually Xhosa but respect the Xhosa way to also undergo the same initiation and become a man alongside their Xhosa friends.

Xhosa circumcision is done by severing the foreskin very quickly without anesthetics.

Check this out: Circumcision increases sexual stamina and satisfaction

Some opinions supporting the idea that circumcision is indeed good for your sex life:

Circumcision increases sexual stamina and satisfaction

To be fair, there is another (much shorter) list of  evidence that the foreskin is needed for pleasure.

Foreskin is important to sexual intercourse and pleasure

Check this out: Bugisu Circumcision

Some interesrting articles about the traditional ritual circumcision practised by the Bugisu.

A Cut Above: Bugisu Boys Become Men

‘Imbalu’ in Bugisu

I particularly liked this statement from the latter:

Traditionally, the Bugisu believed that the removal of the foreskin was a punishment given to men who preyed on other men’s wives. However, when the man recovered from this painful practice, he would go back to his old habits with such skill that other men followed suit.