A product being developed at the Laval University in Quebec.
If it hits the markets, which is likely, it will be able to kill 99.9% of HIV and 90-100% of STDs.
This is a "female condom" which is actually a liquid, solidifying to a gel at body temperature (creating a protective film) and wearing off in approximately 2 hours.
Boy: "Yo baby, lets do it! I forgot protection, but no worries..."
Girl: "Sure if you want, I'll be right back." *Uses invisible condom gel, stays protected, doesn't get preggers*
Boy and Girl: *both happy*